From Middle English, from Old English bræġen (“brain”), from Proto-Germanic *bragnan (“brain”), from Proto-Indo-European *mreghmno- (“skull, brain”), from Proto-Indo-European *mreK- (“marrow, sinciput”). Cognate with Scots braine, brane (“brain”), West Frisian brein (“brain”), Dutch brein (“brain”), Low German brägen (“brain”), Ancient Greek βρεχμος (brechmos, “front part of the skull, top of the head”).
NounBrain (plural Brains)
- The control center of the central nervous system of an animal located in the skull which is responsible for perception, cognition, attention, memory, emotion, and action.
- An intelligent person.
- He was a total brain.
- (English pluralia tantum) A person who provides the intelligence required for something.
- He is the brains behind the scheme.
- (in the plural) Intellect.
- He has a lot of brains.
- 2008 Quaker Action (magazine) Rights trampled in rush to deport immigrant workers, Fall 2008, Vol. 89, No. 3, p. 8:
- "We provided a lot of brains and a lot of heart to the response when it was needed," says Sandra Sanchez, director of AFSC's Immigrants' Voice Program in Des Moines.
- By analogy with a human brain, the part of a machine or computer that performs calculations.
- The computer's brain is capable of millions of calculations a second.
- (brain lobes) brain lobe; frontal lobe, occipital lobe, parietal lobe, temporal lobe (Category: en:Brain) 
- The translations below need to be checked.
- (slang, transitive) To strike (someone) on the head.
- (transitive) To kill (a person) by smashing that person's skull.
- For examples of the usage of this term see the citations page.
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