- brain
- O.E. brægen "brain," from P.Gmc. *bragnam (cf. M.L.G. bregen, O.Fris., Du. brein), from PIE base *mregh-m(n)o- "skull, brain" (cf. Gk. brekhmos "front part of the skull, top of the head"). The custom of using the plural to refer to the substance (literal or figurative), as opposed to the organ, dates from 16c. Figurative sense of "intellectual power" is from late 14c.; meaning "a clever person" is first recorded 1914. The verb meaning "to dash the brains out" is from late 14c. Brain-dead is from 1976, popularized by the Karen Anne Quinlan case (brain death is from 1968); brain teaser is from 1923. Brain stem first recorded 1879, from German. Brain drain is attested from 1963. An O.E. word for "head" was brægnloca, which might be translated as "brain locker." In M.E., Brainsick (O.E. brægenseoc) meant "mad, addled."