barm n : a commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskey [syn: yeast]
Etymology 1From bearm.
Etymology 2From beorma. The cake sense is possibly a shortened form of barmcake, which would be made with yeast as described in that sense. Possibly it is from the báirín breac, a type of cake.
- Foam rising upon beer, or other malt liquors, when fermenting,
and used as leaven in making bread and in brewing; yeast.
- 1882: In 1577 yeast, called barm, is bought at 9d. the pail. — James Edwin Thorold Rogers, A History of Agriculture and Prices in England, Volume 4, p. 620.
- A small flat round, individual loaf, or roll of bread.
Barm, a word derived from the old English for yeast, is the foam, or scum, formed on the top of liquor when fermenting. It was used to leaven bread, or set up fermentation in a new batch of liquor. Barm, as a leaven, has also been made from ground millet combined with must out of wine-tubs and is sometimes used in British baking as a synonym for a natural leaven.
Barm or barm cake is also the preferred terminology for a bread roll that resembles (but is by no means the same as) a hamburger bun (hamburger buns are usually frozen and sold in fast-food outlets, a 'barm cake' is always fresh) in the North-West of the United Kingdom. (e.g.: chip barm, bacon barm, egg barm)
"Barmy"''' is also British slang for "crazy", comparing the foamy texture of barm to the perceived emptiness of such a person's head.