drunkard n.

Old English drincan "to swallow water or other fluid," also "to swallow up, engulf" (class III strong verb; past tense dranc, past participle druncen), from Proto-Germanic *drenkanan (source also of Old Saxon drinkan, Old Frisian drinka, Dutch drinken, Old High German trinkan, German trinken, Old Norse drekka, Gothic drigkan "to drink"), which is of uncertain origin or connections, perhaps from a root meaning "to draw."

Most Indo-European words for this trace to PIE *po(i)- (source of Greek pino, Latin biber, Irish ibim, Old Church Slavonic piti, Russian pit'; see imbibe).

Figurative meaning "take in through the senses" is from late 12c. Especially "to imbibe spiritous liquors" from mid-15c. To drink to "salute in drinking" is by mid-13c. To drink like a fish is recorded from 1744. To drink (someone) under the table "continue drinking and remain (comparatively) sober after others have passed out" is by 1909.

also -art, from Old French -ard, -art, from German -hard, -hart "hardy," forming the second element in many personal names, often used as an intensifier, but in Middle High German and Dutch used as a pejorative element in common nouns, and thus passing into Middle English in bastard, coward, blaffard ("one who stammers"), etc. It thus became a living element in English, as in buzzard, drunkard. The German element is from Proto-Germanic *-hart/*-hard "bold, hardy" (from PIE root *kar- "hard").

past participle and former past tense of drink, used as an adjective from mid-14c. in sense "intoxicated, inebriated." In various expressions, such as drunk as a lord (1891), Drunk as a Wheelbarrow (1709); Chaucer has dronke ... as a Mous (c. 1386). Formerly also, of things, "drenched, saturated" (late 14c.).  The noun meaning "drunken person" is from 1852; earlier this would have been a drunkard. Meaning "a spree, a drinking bout" is by 1779.

Medieval folklore distinguished four successive stages of drunkenness, based on the animals they made men resemble: sheep, lion, ape, sow. Drunk driver "intoxicated operator of a vehicle" is attested by 1912 of automobile drivers; from 1898 of horse-drawn vehicles; by 1894 of railroad engineers; drunken driver is older (by 1770). Drunk-tank "jail cell for drunkards" attested by 1912, American English.