A–M

ABV
Alcohol by volume — the percentage of a drink's total volume that is pure alcohol, and the standard measurement printed on nearly every beer, wine, and spirits label.
Ale
A broad beer category fermented with top-fermenting yeast at warmer temperatures, typically producing fruitier, more complex flavors than the cleaner, crisper profile of a lager.
Attenuation
The percentage of sugar in wort that yeast converts into alcohol and carbon dioxide during fermentation, which determines how sweet, dry, or full-bodied the finished beer tastes.
Barrel-Aged
Beer conditioned for a period in wooden barrels, often ones that previously held bourbon, wine, or sherry, picking up wood, vanilla, and residual spirit character.
Bittering Hops
Hops added early in the boil, where prolonged heat isomerizes and extracts their bitter acids rather than preserving their more delicate aromatic oils.
Bottle Conditioning
A process in which beer is carbonated naturally inside the bottle through a small secondary fermentation, rather than being force-carbonated with injected CO2 before packaging.
Brettanomyces
A wild yeast genus, often called 'Brett,' that produces funky, barnyard, or leathery flavors, used deliberately in some sour and farmhouse beer styles.
Cask Conditioning
A traditional British method of naturally carbonating and serving beer directly from a cask at cellar temperature, without added CO2 pressure or heavy chilling.
Cellaring
Storing beer, usually a higher-alcohol or barrel-aged style, for an extended period to let its flavors mellow and develop, similar to aging wine.
Cider
A fermented beverage made from apple juice, ranging from bone dry to sweet and from still to fully sparkling, depending on the apples and production method used.
Diacetyl
A buttery, butterscotch-like off-flavor in beer caused by yeast byproducts that weren't fully reabsorbed during fermentation.
Draught
Beer served from a keg or cask through a tap, rather than from an individual bottle or can.
Dry Hopping
Adding hops to beer after the boil, typically during or after fermentation, to add aroma and flavor without contributing much additional bitterness.
Esters
Aromatic compounds formed during fermentation that give some beers fruity notes like banana, pear, or apple, with warmer fermentation temperatures generally producing more of them.
Gravity
A measurement of the density of a beer's wort or finished product relative to water, used by brewers to estimate sugar content and potential alcohol.
Growler
A large, resealable jug, typically glass, used to transport draft beer purchased from a brewery or bar for drinking elsewhere.
Head Retention
A beer's ability to maintain a stable foam head over time, influenced by protein content, carbonation, and glass cleanliness.
Hop Schedule
The plan for when and how much hops are added during the brewing process, balancing bitterness, flavor, and aroma contributions.
Hops
The cone-shaped flower of the hop plant, used in brewing to add bitterness, aroma, and flavor, and to act as a natural preservative that helps beer keep longer.
IBU
International Bitterness Units, a scale used to indicate a beer's measured or perceived bitterness from hops, though perceived bitterness can vary with a beer's malt sweetness.
Imperial
A style modifier indicating a stronger, more intensely flavored version of a beer style, such as an imperial stout brewed well above typical strength.
Keeving
A traditional French and English cider- and perry-making technique that naturally clarifies juice and slows its fermentation before it begins, producing a naturally sweeter finished cider.
Kettle Sour
A quick method of souring beer by adding lactic acid bacteria to the wort in the kettle before boiling, rather than souring it slowly in barrels.
Krausen
The thick, foamy head of yeast, hop resins, and proteins that forms on top of beer during the most active stage of fermentation.
Lagering
An extended period of cold storage and slow secondary fermentation used for lager-style beers, giving them their characteristically clean, crisp flavor and smooth carbonation.
Lambic
A traditionally Belgian style of beer spontaneously fermented by wild yeast and bacteria present in the brewery's air, rather than a single cultivated yeast strain, producing tart, funky flavors.
Lauter Tun
The vessel used to separate sweet wort from spent grain after mashing, typically fitted with a slotted false bottom.
Malting
The controlled process of soaking, germinating, and then drying grain to develop the enzymes and flavors needed for brewing, before it is milled and mashed.
Mouthfeel
The physical sensation of a beer in the mouth — thin, full, creamy, or carbonated — separate from its taste or aroma.

N–Z

Nitro
Beer dispensed using nitrogen gas instead of, or alongside, carbon dioxide, producing a tighter, creamier head and a noticeably softer, smoother mouthfeel.
Noble Hops
A group of traditional European hop varieties — including Hallertau, Tettnang, Saaz, and Spalt — prized for mild, refined bitterness and delicate aroma.
Original Gravity
The density of wort measured before fermentation begins, used together with the beer's final gravity reading to calculate its finished alcohol content.
Oxidation
Beer's exposure to oxygen after packaging, which over time produces stale, cardboard-like, or sherry-like off-flavors.
Pasteurization
Heating a finished beer or cider to kill remaining yeast and microorganisms, extending shelf life and stability at some cost to fresh, unpasteurized flavor.
Perry
A fermented beverage made from pear juice, similar to cider but with its own distinct floral, slightly tannic character.
Pilsner Malt
A pale, lightly kilned base malt originally developed in the Czech city of Plzeñ, prized for the clean, bready flavor it gives to light lager styles.
Priming Sugar
A measured amount of sugar added to beer just before bottling to feed a final, small fermentation that naturally carbonates it.
Protein Rest
A pause at a specific, lower temperature during mashing that helps break down proteins, improving a beer's clarity and head retention.
Racking
Transferring beer or cider from one vessel to another, leaving sediment behind, typically done before bottling or before a further conditioning period.
Real Ale
Beer that continues to ferment and condition naturally in the container it's served from, usually a cask, without added carbonation or pasteurization.
Reinheitsgebot
The Bavarian 'purity law' of 1516, which historically restricted beer ingredients to water, barley, and hops, before yeast's role in fermentation was even understood.
Secondary Fermentation
An additional fermentation stage, often carried out in a separate vessel, used to further clarify beer, build carbonation, or develop flavor before final packaging.
Session Beer
A beer intentionally brewed at a lower ABV, meant to be flavorful enough to enjoy while still allowing several to be drunk over a longer session.
Skunking
An off-flavor caused by light exposure breaking down hop compounds, producing an aroma much like a skunk's spray, common in green- or clear-bottled beer.
Sour Beer
A beer deliberately soured using wild yeast, lactic or acetic bacteria, or a blended culture, producing tart, funky, or vinegar-like flavors on purpose.
Sparging
Rinsing the spent grain bed with hot water after mashing to extract the remaining sugars before they're carried forward into the boil.
Steeping
Soaking specialty grains in hot water to extract their color and flavor without needing a full enzymatic mash, common in extract brewing.
Terminal Gravity
The final density reading of a beer once fermentation finishes, used along with the original gravity to calculate the beer's finished ABV.
Top-Fermenting
A fermentation style, characteristic of ales, in which yeast rises to the top of the fermenter and works best at warmer temperatures.
Trappist
A beer legally brewed within the walls of an active Trappist monastery, under monastic supervision, with its proceeds supporting the monastery and charitable causes.
Trub
The sediment of proteins, hop matter, and dead yeast that settles at the bottom of the fermenter or kettle after brewing and fermentation.
Unfiltered
Beer bottled or canned without filtration, retaining suspended yeast and proteins that can add haze, body, and additional flavor compared with a filtered version.
Wheat Beer
A beer brewed with a substantial proportion of wheat alongside barley, typically producing a hazy appearance and a soft, sometimes fruity or spicy character.
Whirlpool
A step after the boil in which hot wort is stirred into a vortex, collecting trub in the center so clearer wort can be drawn off.
Wild Fermentation
Fermentation carried out by yeast and bacteria naturally present in the environment, rather than a single cultivated strain deliberately pitched by the brewer.
Wort
The sugary liquid extracted from malted grain before fermentation, boiled with hops and then cooled, which yeast later converts into finished beer.
Yeast Strain
The specific variety of yeast used in fermentation, which strongly influences a beer's flavor, aroma, and mouthfeel, sometimes more than the recipe's grain bill does.
Zymurgy
The branch of applied chemistry dealing with fermentation, encompassing brewing, winemaking, and distilling, and the root of the American Homebrewers Association's magazine name.
  • Glossary
  • Beer
  • Cider

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