What does decaf mean?
Decaf is short for decaffeinated coffee: coffee from which most of the naturally occurring caffeine has been extracted, typically by treating green beans with water, solvents, or carbon dioxide. The word functions primarily as a noun, referring either to the substance itself — usually as an uncountable mass noun — or, informally, to a single cup or order of it, as in 'I'll have a decaf.' It also appears frequently as an attributive adjective in phrases like 'decaf coffee,' though this use derives directly from its role as a shortened form of 'decaffeinated.' Decaf carries no strong connotation beyond its association with avoiding stimulants; it is often chosen for health reasons, pregnancy, evening consumption, or personal preference. First recorded commercially in the early twentieth century following Ludwig Roselius's patented decaffeination process, the clipped form has become so entrenched in everyday speech that many speakers rarely encounter the longer original term outside packaging labels.
nounDecaf is coffee from which most of the caffeine has been removed. It is also used informally as an uncountable mass noun for a cup or serving of such coffee.
- Coffee that has had most of its caffeine removed.
- (Informal) A cup, serving, or order of decaffeinated coffee.
"She ordered a decaf because it was already late in the evening."
"He switched to decaf after his doctor advised him to cut back on caffeine."
"Can I get a large decaf with oat milk?"
The plural applies only when counting servings or orders of decaffeinated coffee; as a mass noun referring to the substance, decaf is normally uncountable.
"The waiter brought out three decafs and a pot of tea."
The first decaf process was invented after a German merchant's claim that his father's death was linked to drinking too much coffee — leading him to patent caffeine removal in 1906.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of decaf
Decaf is a clipping of 'decaffeinated coffee,' formed from the prefix 'de-' (indicating removal) combined with 'caffeine.' Caffeine itself derives from German 'Koffein', coined around the mid-nineteenth century from 'Kaffee' (coffee), which traces ultimately to Arabic 'qahwa'. Decaffeination as an industrial process was developed in the early twentieth century by the German coffee merchant Ludwig Roselius, whose method was commercialized under the brand name Sanka.
How decaf is actually used
Decaf is informal-to-neutral register and widely used in both British and American English. It commonly appears as an attributive modifier before 'coffee' and as a countable noun when ordering a single serving ('a decaf'). The full form 'decaffeinated' is preferred in formal writing.
Easily confused with decaf
As an attributive modifier ('decaf coffee') it functions adjectivally, but as a standalone word it is the noun for the drink itself.