Butt
Middle English: from Old French boter, of Germanic origin.
wiktionary
From Middle English but, butte(“goal, mark, butt of land”), from Old English byt, bytt(“small piece of land”) and *butt (attested in diminutive Old English buttuc(“end, small piece of land”) > English buttock), from Proto-Germanic *buttaz(“end, piece”), from Proto-Indo-European *bʰudʰnós(“bottom”), later thematic variant of Proto-Indo-European *bʰudʰmḗn ~ *bʰudʰn-, perhaps from Proto-Indo-European *dʰewbʰ-(“deep”).
Cognate with Norwegian butt(“stump, block”), Icelandic bútur(“piece, fragment”), Low German butt(“blunt, clumsy”). Influenced by Old French but, butte(“but, mark”), ultimately from the same Germanic source. Compare also Albanian bythë(“buttocks”), Ancient Greek πυθμήν(puthmḗn, “bottom of vessel”), Latin fundus(“bottom”) and Sanskrit बुध्न(budhná, “bottom”), from the same Proto-Indo-European root. Related to bottom, boot.
From Middle English butten, from Anglo-Norman buter, boter(“to push, butt, strike”), from Frankish *bautan(“to hit, beat”), from Proto-Germanic *bautaną(“to beat, push”), from Proto-Indo-European *bʰewd-(“to beat, push, strike”). Cognate with Old English bēatan(“to beat”). More at beat.
From Middle English bit, bitte, bytte, butte(“leather bottle”), from Old English bytt, byt and Old French boute(“cask”) and other etymologies on this page.
From Middle English but, butte, botte(“flounder; plaice; turbot”), possibly derived from sense 1(“blunt end”), meaning "blunt-headed fish." Compare Dutch bot and the second element of English halibut.
Cognate with West Frisian bot, German Low German Butt, German Butt, Butte, Swedish butta.
(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.)
etymonline
butt (n.1)
"thick end," c. 1400, butte, which probably is related to Middle Dutch and Dutch bot, Low German butt "blunt, dull," Old Norse bauta, from Proto-Germanic *buttan, from PIE root *bhau- "to strike." Or related somehow to Old English buttuc "end, small piece of land," and Old Norse butr "short," from Proto-Germanic *butaz, which is from the same PIE root. Also probably mixed with Old French bot "extremity, end," which also is from Germanic (compare butt (n.3)). Meaning "remainder of a smoked cigarette" first recorded 1847.
butt (n.2)
"liquor barrel, cask for wine or ale," late 14c., from Anglo-French but and Old French bot "barrel, wine-skin" (14c., Modern French botte), from Late Latin buttis "cask" (see bottle (n.)). Cognate with Spanish and Portuguese bota, Italian botte. Usually a cask holding 108 to 140 gallons, or roughly two hogsheads; at one time a butt was a legal measure, but it varied greatly and the subject is a complicated one (see notes in Century Dictionary).
butt (n.3)
"target of a joke, object of ridicule," 1610s, from earlier sense "target for shooting practice, turf-covered mound against which an archery target was set," (mid-14c.), from Old French but "aim, goal, end, target" of an arrow, etc. (13c.), which seems to be a fusion of Old French words for "end" (bot) and "aim, goal" (but), both ultimately from Germanic. The latter is from Frankish *but "stump, stock, block," or some other Germanic source (compare Old Norse butr "log of wood"), which would connect it with butt (n.1).
butt (v.)
"hit with the head, strike by thrusting" (as with the end of a beam or thick stick), c. 1200, from Anglo-French buter, Old French boter "to push, shove, knock; to thrust against," from Frankish or another Germanic source (compare Old Norse bauta, Low German boten "to strike, beat"), from Proto-Germanic *butan, from PIE root *bhau- "to strike."
Meaning "to join at the end, be contiguous" is from 1660s, partly a shortening of abut. To butt in "rudely intrude" is American English slang, attested from 1900. Related: Butted; butting.
butt (n.4)
"flat fish," c. 1300, a general Germanic name applied to various kinds of flat fishes (Old Swedish but "flatfish," German Butte, Dutch bot), from Proto-Germanic *butt-, name for a flat fish, from PIE root *bhau- "to strike." "Hence butt-woman, who sells these, a fish-wife." [OED]
butt (n.5)
"a push or thrust with the head," 1640s, from butt (v.).
butt (n.6)
"posterior, buttocks, rump," from mid-15c. in cookery, in reference to animal parts, probably from or related to butt (n.1) "thick end," or short for buttock. In modern use chiefly of humans, probably an independent derivation, attested by c. 1860 in U.S. slang.
