ABV
Alcohol by volume; the measure of how much ethanol is contained in a given volume of a liquid, expressed as a percentage. See also Proof.
Aftershots
The final spirit produced from a spirit still at the end of the distillation process. These fusel oils are low in alcohol and can be discarded or redistilled. Also known as feints or tails.
Age statement
The number of years that distilled spirits have been stored in oak containers prior to bottling, as stated on the bottle. An age statement is required for American whiskeys aged less than 4 years. This also applies to blended whiskies if the youngest whisky in the blend has been aged less than 4 years. For nearly all whisky, the age statement must state the youngest whisky in the blend.
Angels' Share
The amount of liquid that evapourates from the barrel during the maturationprocess. This varies according to factors like heat and humidity, and the percentage lost is higher in warmer regions.
Backset
In American whiskey, an acidic liquid strained from the mash after the primary distillation. It's typically added back to the mash tub or fermenter to help catalyze fermentation and ward off bacterial contamination. Also known as sour mash.
Barley
A cereal grain used in the production of whisk(e)y. Malted barley is required to make malt whisky, although unmalted barley can be used to make other types of whisky.
Barrel
A general term for a type of wooden cask used in the storage and maturation of whisk(e)y. The term can also refer to standard units of measurement for different products in different regions. A standard bourbon barrel measures 200 liters, or 53 gallons. The Scotch Whisky Association defines an American barrel as measuring between 173 and 191 liters.
Barrel proof
Refers to whisky that's bottled at or very near itsalcohol strength when it emerged from the barrel at the end of maturation, undiluted by added water. In the U.S., TTB regulations require "barrel proof" whiskey to be bottled at not more than two degrees lower than the proof established at the time the spirits were gauged for tax determination. See also Cask strength.
Bere barley
One of the oldest varieties of barley in Britain, occasionally used for making malt whisky. These days, it's grown mainly in the north of Scotland, including on Orkney and Shetland.
Blend
A combination of two or more spirits. In the United States, a blended whiskey must contain at least 20% straight whiskey or a blend of straight whiskeys, while the remainder can consist of non-straight whiskey, neutral spirits, or both. In Ireland, a blended whiskey is a mixture of any two or more of the styles of malt, pot still, and grain whiskey. In Scotland, blended whisky is a mixture of whiskies from different distilleries, typically using both malt and grain whiskies. Blended malt whisky mixes single malts from a number of distilleries, while blended grain whisky mixes single grains from a number of distilleries.
Blended malt
In Scotland, a blend of malt whiskies from at least two distilleries; previously referred to as a vatted malt.
Bottled in bond
American spirits, most often bourbon or rye, produced within the regulations of the Bottled-in-Bond Act of 1897. These spirits must be produced in a single distillation season by a single distillery, mature in a U.S. bonded warehouse for at least 4 years, and be bottled at 50% ABV. Bottled in bond whiskey may also be referred to as bonded whiskey.
Bourbon
American whiskey made from a mash of at least 51% corn, with the remainder being any other grain. Rye and wheat are most common, and most contain a small amount of malted barley to aid in the fermentation process. It must be distilled to no more than 80% ABV, aged in charred new American oak containers with an entry ABV of no more than 62.5%, and bottled at no less than 40% ABV. Bourbon may be produced anywhere in the United States. For more information, see "Instant Expert: Bourbon, Rye, and American Whiskey."
Bung
The stopper used to close a barrel or cask.
Butt
In Scotch whisky, a cask measuring 500 liters.
Campbeltown
A whisky-producing region of Scotland, or a term describing whisky from this region. Historically a major center of distillation, Campbeltown now has only three working distilleries.
Canadian whisky
Often referred to as "rye" even when no rye grain is used in the whisky-making process. Canadian whisky may be made of any cereal grain and a finished product typically blends several types of whisky—such as wheat, corn, and rye—which are all milled, mashed, fermented, distilled, and matured separately. In addition, Canadian regulations state that Canadian whisky must be aged in "small wood" (less than 700 liters) for at least 3 years; undergo mashing, distilling, and aging in Canada; contain no less than 40% ABV; and possess the aroma, taste, and character generally attributed to Canadian whisky. Canadian whisky may contain added caramel colouring and flavouring; the law allows for up to 9.09% of the blend to be added spirits aged at least 2 years or wine. For more information, see "Instant Expert: Canadian Whisky."
Caramel colouring
A flavourless, odorless colourant made from sugar that darkens the hue of the whisky. It can legally be added to scotch and many other whiskies, but not to bourbon or straight American whiskeys. Sometimes referred to by the name e150a.
Cask
A general term for all types of oak vessels used in the storage and maturation of whisky. See also Barrel.
Cask strength
Refers to whisky that's bottled at the same alcohol strength it was when it was removed from the barrel; undiluted by water before bottling. See also barrel proof.
Charcoal mellowing
The act of filtering unaged whiskey through maple charcoal before going into the barrel—a requirement for Tennessee whisky. See also Lincoln County Process.
Charring
The act of burning the inside of a barrel as part of the coopering process. The amount of char impacts the colour and flavour of the resulting aged whisky. Required for bourbon and Tennessee whiskey, among other American whiskeys.
Chill filtered
Refers to whisky that has been cooled and passed through a filter in order to remove particles that would affect its cosmetic appearance. Whiskies that do not undergo this process often advertise that they are non-chill filtered.
Chocolate malt
Malted barley that has been dried at higher temperatures, which darkens the colour and releases cocoa flavours.
Coffey still
Refers to the column still design patented by Aeneas Coffey in 1830. A more efficient alternative to the pot still, it is capable of continuous distillation by reheating the liquid, rather than requiring distillation in batches, and can produce higher ABV spirits than pot stills. The device consists of two columns which contain a number of compartments separated by heated plates. The plates are perforated with small holes to permit the upward passage of steam and spirit vapour, which is condensed to become spirits.
Column still
A more efficient alternative to the pot still, it is capable of continuous distillation by reheating the liquid, rather than requiring distillation in batches, and can produce higher ABV spirits than pot stills. The device consists of two columns which contain a number of compartments separated by heated plates. The plates are perforated with small holes to permit the upward passage of steam and spirit vapour, which is condensed to become spirits. Often referred to as a continuous still or Coffey still.
Condenser
A component in the distillation apparatus that converts the spirits from a gas to a liquid through cooling, either as a coiled tube submerged in a tub of water (worm tub) or a vertical tube through which water is piped (shell and tube condenser).
Congener
Flavourful chemical compounds, including aldehydes, esters, acids, and higher alcohols, produced during fermentation and maturation.
Continuous still
Refers to the column still design patented by Aeneas Coffey in 1830. A more efficient alternative to the pot still, it is capable of continuous distillation by reheating the liquid, rather than requiring distillation in batches, and can produce higher ABV spirits than pot stills. The device consists of two columns which contain a number of compartments separated by heated plates. The plates are perforated with small holes to permit the upward passage of steam and spirit vapour, which is condensed to become spirits. Often referred to as a Coffey still or column still.
Cooper
One who makes barrels or casks. Also refers to the process of making the barrels/casks, as in "coopering a barrel."
Cooperage
A business or premises that produces barrels or casks. Also sometimes used to refer to casks or barrels, e.g., "aged in new cooperage."
Corn
A grain used in spirits production. Corn is the primary grain in bourbon whiskey, required to represent at least 51% of the mashbill.
Corn whiskey
American whiskey made with a mash consisting of a minimum of 80% corn and distilled to a maximum of 80% ABV. Corn whiskey may be matured in used or uncharred oak containers, but does not require barrel aging. It is subject to regulatory requirements, setting it apart from moonshine. A variant known as straight corn whiskey is aged in used or uncharred oak barrels for 2 or more years.
Cut
The middle, best section of the distillate, often called the heart, which goes into the cask/barrel. Also refers to the process itself, i.e. "making the cut."
Distillation
The process of physically separating alcohol from water using heat. Alcohol has a lower vaporisation temperature than water, so liquid alcohol turns to vapour at a lower temperature. The alcohol vapour is then recondensed to a liquid as it is cooled. For more information, see
Distiller's beer
The alcoholic liquid produced through fermentation that is then distilled to produce a spirit. It generally has 7-10% ABV. See also Wash.
Double-distilled
Distilling a spirit twice using a batch distillation method. Most Scotch malt whisky is double-distilled.
Doubler
In American whiskey distilling, a type of pot still used for the second round of distillation. A doubler receives spirit that has already been cooled into a liquid, whereas a thumper receives vapour.
Draff
A term used in Scotland for the remnants of grain drained from the wash following fermentation. Often used as animal feed.
Dram
A Scottish term for a glass of whisky; or a measurement equal to 1/8 fl oz.
Dunnage warehouse
A traditional warehouse, typically found in Scotland and Ireland, built with an earth floor and brick or stone walls.
Ethanol
A potable alcohol found in whisky and other fermented and distilled beverages, also known as ethyl alcohol. Produced as a by-product of the fermentation of sugar by yeast.
Feints
The final spirit produced from a spirit still at the end of the distillation process. These fuel oils are low in alcohol and can be discarded or redistilled. Also known as after shots or tails.
Fermentation
A metabolic process where yeast feeds on sugar, creating acids, gases, and/or alcohol as by-products. All whisky-making includes a fermentation process before distillation.
Fermenter
The container in which mash is fermented with yeast into an alcoholic wash before distillation. See also Washback.
Finish
The aftertaste that lingers on the palate after consuming whisky. This is described both in terms of flavour characteristics and length. Can also refer to the process of cask finishing, where fully mature whisky is transferred from its original maturation cask to a different cask, usually for a short period of time, with the intention of imparting specific flavours onto the final product.
First-fill
A cask that has previously been used to age sherry, port, bourbon, or other aged wines or spirits, and is now being used to age another whisky for the first time. First-fill casks impart the most prominent characteristics of the previous liquid on to the whisky, while each subsequent fill will receive progressively less influence. See also Refill.
Flavoured whisky
Whisky with additives, such as artificial flavouring or natural ingredients like fruit or honey, that change the taste. Often bottled below 40% ABV, the minimum proof for most whiskies.
Flavouring grain
In bourbon, refers to the secondary grain, such as rye or wheat, which has an effect on flavour profile if present in a large amount.
Floor malting
A traditional process where barley is germinated on a floor, turned by hand. Mostly replaced with more efficient modern processes like drum malting. The germination process converts barley's starches to fermentable sugars, and the process is stopped by drying with heat.
Foreshots
The first spirit to come from a still in the second distillation, high in methanol and other volatile compounds. It is either discarded or redistilled. See also Heads.
Grain whisky
A spirit made from grains such as corn, wheat, or rye that has typically been distilled in a column still. Some countries, like Scotland and Ireland, have regulations defining grain whisky more specifically.
Green malt
Germinated barley that has not been dried.
Grist
A rough flour made by milling the grains used for fermentation. Water is added to form the wort.
Heads
The first spirit to come from a still in the second distillation, high in methanol and other volatile compounds. It is either discarded or redistilled. See also Foreshots.
Heart
The middle, best section of the distillate, often called the middle cut, which goes into the cask/barrel.
High rye
Refers to a bourbon containing a large percentage of rye in the mashbill—often around 20-35%.
High wines
A spirit that has undergone its final distillation and is ready for dilution and/or maturation.
Highlands
A whisky-producing region in the northern part of Scotland, or, a term describing whisky from this region.
Hogshead
In Scotch whisky, a cask with a volume capacity between 250 and 305 liters.
Independent bottler
A company that purchases, bottles, and sells whisky from outside distilleries. They may blend these whiskies, offer them under another name, or—for many Scottish independent bottlers—sell the whisky under the original distiller's name, with the bottler's name noted.
Intermediate still
In triple-distillation using pot stills, the still used after spirit emerges from the wash still and before it goes into the spirit still.
Irish whiskey
Whiskey made and matured anywhere in Ireland and Northern Ireland. Irish whiskey must contain malted barley and may include other unmalted cereal grains, must be distilled to an ABV no higher than 94.8%, and must mature in wooden casks that are no larger than 700 liters. It can contain no additional additives other than water and caramel colouring, must display the typical characteristics of whiskey, and be bottled at no less than 40% ABV. Irish whiskeys are often triple distilled in pot stills, but can be double distilled in a style more similar to Scotch whisky and can also be made in column stills.
Islands
Any of the whisky-producing islands of Scotland (generally excepting Islay as a distinct region), or a term describing whisky from these regions.
Islay
A whisky-producing island off the west coast of Scotland, or a term describing whisky from this island. Islay whiskies are generally heavily peated.
Japanese whisky
Whisky produced in Japan. There are few regulations governing its production; however, many Japanese whiskies resemble single malt or blended Scotch whiskies in style. For more information, see "Instant Expert: Japanese Whisky."
Jigger
A bartending device used for measuring a predetermined small volume of spirits. May refer to a standard measurement of spirits, typically 1.5 fl. oz.
Kiln
An oven used to dry green malt, which stops the germination process started by malting.
Lincoln County Process
A technique used in the production of Tennessee whiskey. The unaged spirit is filtered through sugar maple charcoal before going into the barrel. See also Charcoal mellowing.
Low wines
A distillate that lacks sufficient alcohol by volume to produce a finished spirit and requires additional distillation.
Lowlands
A whisky-producing region in the south of Scotland, or a term describing whisky from this region.
Lyne arm
In pot distillation, the conduit connecting the head of the still to the condensing unit.
Malt
Germinated grain (usually barley) that has been heated to stop growth. Also a term to describe whisky made from malted barley.
Malt whisky
Whisky made from malted barley. In the United States, a malt whiskey must be made from a mashbill of at least 51% malted barley. In Scotland and Ireland, malt whiskymust be made from 100% malted barley and be distilled in a pot still.
Malted
A term describing grain—usually barley—that has been germinated and then heated to stop growth. This process secretes an enzyme that converts the grain's starches to fermentable sugars.
Marrying
A period after blending and before bottling when the whisky rests, often in a neutral vat. Marrying is not a requirement, but some producers believe it results in a better integrated whisky.
Mash
A liquid composed of grist mixed with hot water, which helps extract sugars before the yeast is added to begin fermentation. See also Wort. For more information, see "How To Make Whisky."
Mash tub/tun
The vessel where grist is combined with hot water to convert the starches into fermentable sugars.
Mashbill
In the United States, the recipe of different grains used to make whiskey.
Master blender
The person responsible for deciding which casks or other lots of spirits go into a batch to achieve a specific flavour profile. Not a regulated term.
Master distiller
The person responsible for dictating distillation practices at a distillery. This term is most often used to describe professionals with many years of experience producing spirits, but as it is unregulated, may apply to any individual in charge of distilling.
Maturation
The process by which a spirit changes as it spends time in a cask. This process fundamentally alters the taste profile of the spirit, imparting character from the cask, as well as reducing the sharper characteristics of the distillate. Nearly all whiskies are aged in wood—usually oak—containers.
Middle cut
The middle, best section of the distillate, often called the heart, which goes into the cask/barrel.
Moonshine
Illicit distilled spirits manufactured by unlicensed individuals without payment of excise tax. Generally, a high-proof, unaged spirit, moonshine was particularly significant in Appalachia during Prohibition, when distillation was often done under cover of night. Some legally produced white whiskey simulating the style is sold under the name moonshine.
Mothballed
A distillery that exists intact but is no longer in operation, also referred to as "silent."
Mouthfeel
The perception of viscosity, texture, and other sensations in the mouth used as descriptors in tasting.
NAS
Stands for "no age statement" or "non-age statement." Whisky that does not make a claim as to how long it has been aged, though it must still meet minimum legal requirements where applicable. Due to whisky's growing popularity and the long lead times required to produce aged stock, NAS offerings are increasingly common.
NDP
Short for non-distiller producer. A producer that does not distill, but instead purchases whisky from a distillery to sell under its own brand name.
Neat
Serving spirits without the addition of ice, water, or other mixers.
Neck
The narrow top section of a pot still leading to the lyne arm.
New make
Whisky that has just come off the still. In the U.S. it's often referred to as white dog.
No age statement
Also referred to as NAS. Whisky that does not make a claim as to how long it has been aged, though it must still meet minimum legal requirements where applicable. Due to whisky's growing popularity and the long lead times required to produce aged stock, NAS offerings are increasingly common.
Non-chill filtered
Whisky that has not undergone chill filtration, which consists of being cooled and passed through a filter in order to remove particles that would affect its cosmetic appearance. Whiskies that do not undergo this process often advertise that they are non-chill filtered, and may have some cloudiness when chilled or when water or ice is added.
Non-distiller producer
A producer that does not distill, but instead purchases whisky from a distillery to sell under its own brand name. Often abbreviated as NDP.
Nose
The aroma of a spirit; or the act of smelling a spirit.
On the rocks
Serving spirits with ice cubes.
Oxidation
The change in characteristics caused by exposure to air. Oxidation is an important part of the cask maturation process. It can also affect a bottled whisky once opened, causing gradual shifts in flavour and aroma.
Pagoda roof
A distinctive style of Scottish distillery chimney, modelled after Chinese architecture, used to improve air flow for the smoke used in drying malted barley.
Peat
Densely compressed, decayed vegetation cut from bogs and dried, then used in the malting process as a smoke-producing fuel that both dries the barley and imparts a distinct flavour. Peat smoke is used in the production of certain Scotch whiskies, including many from Islay. It is used in the production of some whiskies from other countries as well, including Ireland, India, Japan, and the United States. Levels of "peatiness" in whisky are measured in phenol parts per million, or PPM.
Phenols
A class of chemical compounds produced by using peat in the malting process, absorbed by the barley being dried. Phenols can be measured in both malted barley and in the final spirit, using a unit called PPM (phenol parts per million).
Pipette
A glass tool used to add water by the drop into a glass of whisky, or a tubular tool used to remove small quantities of whisky from a barrel for sampling.
Poitín
A traditional Irish spirit which translates to "little pot." Historically produced illicitly, it is now regulated by Irish law. It can be produced from a number of ingredients, including grain, potatoes, and sugar beet molasses, and is unaged. Pronounced put-cheen.
Pot ale
In Scotland, the residue left in the still after the production of low wines, following the first distillation. Often used for animal feed.
Pot still
A traditional type of copper still used in batch distillation. In Scotland and Ireland, malt whisky must be made in a pot still. "Pot still" may also refer to a type of Irish whiskey, made from a mash of a minimum 30% malted and a minimum 30% unmalted barley, with up to 5% of other cereals added, that is distilled in pot stills. To learn more, see "How To Make Whisky."
PPM
A measurement of phenol parts per million, which indicates the presence of peat influence in malted barley or whisky.
Proof
In the U.S., the ethanol content of a spirit at 60 degrees Fahrenheit. The number is equal to double the spirit's ABV.
Quaich
A traditional, two-handled Scottish drinking cup.
Quarter cask
In Scotland, a cask with a capacity of 127-159 liters.
Rackhouse/rickhouse
In the U.S., a warehouse used for storing barrels of aging whiskey. Barrels are stored on ricks, stacked several high. The materials that the building is constructed from, as well as the location of the barrel in the building, can affect the maturation process.
Refill
A cask that has been previously used to mature whisky and refilled a second time (or more). See also First-fill.
Reflux
Alcohol vapour that returns to the still rather than traveling to the condenser, thus being redistilled. The angle of the lyne arm can determine levels of reflux.
Rick
The structures that barrels sit on in a rickhouse/rackhouse.
Rye
A grain used in whisky production that imparts spicy characteristics to the spirit. In the U.S., refers to whiskey made from a mashbill of at least 51% rye, distilled to a maximum of 80% ABV, aged in new, charred oak containers with a maximum barrel entry of 62.5% ABV, and bottled at a minimum of 40% ABV. Canadian whisky is sometimes referred to as rye, even if no rye grain was used in its production.
Saladin box
A vessel in which barley is germinated before malting that uses a system of turning screws to agitate the grain. Invented in the late 19th century, it offered a mechanical alternative to hand turning.
Scotch
Whisky made in Scotland. Scottish regulations dictate different types of whisky, including malt, grain, and blended whiskies, which must conform to certain standards: made of only water and malted barley, and may include other cereal grains; be mashed, fermented, distilled to no more than 94.5% ABV, and matured in oak casks not exceeding 700 liters for a minimum of 3 years in Scotland; not contain additives other than water and caramel colouring; be bottled at no less than 40% ABV; and exhibit the characteristic traits of whisky.
Shell and tube condenser
A component in the distillation apparatus that converts the spirit from a gas to a liquid by running the vapour through a copper tube that is cooled by a system of cold water-fed small copper pipes.
Sherry
A type of fortified wine from the region of Jerez in southern Spain; can also refer to the region itself (Sherry is the anglicized version of Jerez). Sherry casks are often used for whisky maturation, imparting characteristics of the wine into the final spirit.
Silent
A distillery that exists intact but is no longer in operation, also referred to as "mothballed."
Silent season
An annual period when a distillery stops production, which is generally used for maintenance and repairs.
Single cask
Whisky bottled directly from a single cask or barrel without any blending. Often but not always bottled at cask strength.
Single grain whisky
Grain whisky from a single distillery; a regulated term in Scotland and Ireland. These lighter-bodied spirits are most often combined with malt whiskies to create blended whisky, although some are offered as bottlings on their own. Single grain whisky is primarily made from cereal grains other than malted barley, such as wheat or corn, and is typically made in a column still.
Single malt whisky
Whisky made from 100% malted barley (or very occasionally other malted grains, such as rye) and produced at a single distillery, typically using pot stills. In Scotland and Ireland, single malt is a regulated term that must conform to certain guidelines. Japan, India, the United States, and many other countries are increasingly producing single malt whisky.
Single pot still
Pot still Irish whiskey is made from a mash of a minimum 30% malted and a minimum 30% unmalted barley, with up to 5% of other cereals added, and is distilled in pot stills. Single pot still whiskey comes from only one distillery. For more information, see Instant Expert: Irish Whiskey.
Sláinte
A Gaelic toast that translates to "health" commonly used in Ireland and Scotland. Pronounced slanj or slan-juh.
Small barrel
Not a regulated term, but generally refers to any barrel less than the standard 53 gallons, often used by new distilleries as a way to mature whisky faster, since the surface area to volume ratio is greater than in full-size barrels.
Small batch
A term that is not legally defined, often used in marketing to suggest any product made in lesser quantities than the distiller's standard offerings.
Solera
A maturation process that involves partial emptying and refilling of casks to achieve an unbroken lineage of fractional blending. The practice comes from the sherry production process, but has been increasingly used by whisky makers.
Sour mash
In American whiskey, a process that uses leftover mash from a previous batch to start the fermentation of a new batch; or a term identifying whiskey made using this process. Also referred to as backset.
Sourced
Refers to whisky purchased from a distiller by a third party and then bottled as a distinct brand. May be blended with other whiskies.
Speyside
A whisky-producing region in Scotland alongside the Spey River, or a term describing whisky from this region. Speyside contains more than half of Scotland's malt whisky distilleries.
Spirit safe
A locked box with a glass front that allows the distiller to watch the spirit leaving the still, measure certain characteristics, such as ABV and temperature, and divert the emerging spirit to different locations as needed. Originally conceived in Scotland to ensure all production was accountable for taxation and prevent illicit sampling.
Spirit still
In double-distillation using pot stills, the still that distils the low wines.
Still
The apparatus used to distill spirits by vaporising alcohols to separate them from water. Stills are usually made of copper, which helps strip spirits of unwanted flavour and aroma compounds. The two most common types are pot stills and column stills.
Straight
Refers to American whiskey made from a grain mash, distilled to no more than 80% ABV, and aged for at least 2 years after entering the barrel at an ABV of no more than 62.5%. The only modifications allowed are the addition of water and mixing whiskeys from different barrels—no flavouring or colourants may be added. Straight whiskey can be a blend of different straight whiskeys, as long as they are from the same state. If any whiskeys from the blend are less than 4 years old, an exact age statement is required on the bottle. For more information, see "Instant Expert: Bourbon, Rye and American Whiskey."
Sweet mash
A mash made without the use of backset/sour mash as a starter for fermentation, instead using only fresh yeast.
Tails
The final spirit produced from a spirit still at the end of the distillation process. These fuel oils are low in alcohol and can be discarded or redistilled. Also knowns aftershots or feints.
Tennessee whiskey
A whiskey made in Tennessee, meeting the same legal requirements as a bourbon, with the added requirement of filtration through sugar maple charcoal, referred to as the Lincoln County Process (with the exception of one distillery, Prichard's).
Terroir
The total environment of any agricultural site, and the overall influence that a specific region, distillery, or site, due to climate, weather, or other environmental factors, imparts to a wine or spirit.
Thumper
In American whiskey distilling, a type of pot still used for the second round of distillation. A thumper receives alcohol vapour, whereas a doubler receives spirit that has already been cooled into a liquid.
Triple-distilled
A spirit that has been distilled three times in a pot still. Often used in Irish whiskey and some Lowlands Scotch whisky. The additional distillation results in a lighter spirit.
Uisge beatha
The Gaelic term for "water of life," and the origin of the word whisky.
Underback
A vessel used to store wort after it has drained from the mash tun and before transferring it to the washbacks for fermentation. A distillery may use the same mash multiple times, mixing it with water of increasing temperatures to extract as much sugar as possible, draining the wort from each batch into the under back in between mashes.
Unmalted
Grain, often referring to barley specifically, that has not undergone the malting process. Irish whiskeys sometimes use a combination of malted and unmalted barley.
Valinch
A tubular tool used to remove small quantities of whisky from a barrel, usually for sampling.
Warehouse
A building used for storing barrels of aging whisky. The materials that the building is constructed from, as well as the location of the barrel in the building, can affect the maturation process. In the U.S., warehouses are often called rickhouses or rackhouses. In Scotland and Ireland, dunnage warehouses are common.
Wash
The alcoholic liquid produced through fermentation that is then distilled to produce a spirit. It generally has 7-10% ABV. See also Distiller's beer.
Wash still
In pot distillation, the first still that distils the wash.
Washback
The container in which wort or mash is fermented through the addition of yeast before distillation. See also Fermenter.
Wheat whiskey
In the U.S., a whiskey with a mashbill composed of at least 51% wheat, distilled to no more than 80% ABV, aged in charred new American oak containers with an entry ABV of no more than 62.5%, and bottled at no less than 40% ABV. For more information, see "Instant Expert: Bourbon, Rye, and American Whiskey."
Wheated bourbon
A bourbon made with wheat as a dominant secondary ingredient. These whiskeys often have a delicate flavour and can be referred to as "wheaters."
Whiskey
A distilled spirit made from fermented grain and typically matured in wooden containers for some period of time. Whisky can be made anywhere in the world. Certain countries—like Scotland, Ireland, the United States, and Canada—have regulations that govern its production. Also spelled "whisky."
Whisky
A distilled spirit made from fermented grain and typically matured in wooden containers for some period of time. Whisky can be made anywhere in the world. Certain countries—like Scotland, Ireland, the United States, and Canada—have regulations that govern its production. Also spelled "whiskey."
Whisky thief
A tubular tool used to remove small quantities of whisk(e)y from a barrel, usually for sampling.
White dog
Whisky that has just come off the still; also referred to as new make.
Worm tub
A component in the distillation apparatus that converts the spirit from a gas to a liquid by running the vapour through a copper tube set in a pool of cold water. Although most distilleries now use shell and tube condensers, old-fashioned worm tubs can still be found.
Wort
A liquid composed of grist mixed with hot water, which helps extract sugars before the yeast is added to begin fermentation. Wort is mash that has been strained of solids. For more information, see "How To Make Whisky."
Yeast
A microorganism that consumes sugars and expels ethanol and CO2, used in the production of potable alcohol.