O.E. heafod "top of the body," also "upper end of a slope," also "chief person, leader, ruler," from P.Gmc. *khaubuthan (cf. O.S. hobid, O.N. hofuš, O.Fris. haved, Ger. Haupt, Goth. haubiž "head"), from PIE *kauput- "head" (cf. Skt. kaput-, L. caput "head"), also "bowl" (as in skull). Modern spelling is c.1420, representing what was then a long vowel (as in heat). Meaning "obverse of a coin" is from 1684; meaning "foam on a mug of beer" is first attested 1545; meaning "toilet" is from 1748, based on location of crew toilet in the bow (or head) of a ship. Synechdochic use for "person" (as in head count) is first attested 1535; of cattle, etc., in this sense from 1513. To give head "perform fellatio" is from 1950s. Meaning "drug addict" (usually in a compound with the preferred drug as the first element) is from 1911. The verb head "to shape one's course toward" (1835) was originally nautical. Header "head-first dive or plunge" first attested 1849. Headlight is from 1861, originally of ships and locomotives. Headquarters is from 1647. Headstrong "determined to have one's way" is from 1398. Headroom "space above the head" first recorded 1851. Headphone is 1914, with second element extracted from telephone. Phrase head over heels is "a curious perversion" [Weekley] of M.E. heels over head. Phrase heads will roll "people will be punished" (1930) translates Adolf Hitler.