also bunghole, "hole in a cask through which is it filled, closed by a stopper," 1570s, from bung (n.) + hole (n.). Sense extended to "anus" by c. 1600.
Entries linking to bung-hole
bung n.
mid-15c., "large stopper for a cask," of uncertain origin, perhaps from Middle Dutch bonge "stopper;" or perhaps from French bonde "bung, bunghole" (15c.), which may be of Germanic origin (or the Germanic words may be borrowed from Romanic), or it may be from Gaulish *bunda (compare Old Irish bonn, Gaelic bonn, Welsh bon "base, sole of the foot"). It is possible that either or both of these sources is ultimately from Latin puncta in the sense of "hole" (from PIE root *peuk- "to prick"). Transferred to the cask-mouth itself (also bung-hole) from 1570s.
hole n.
Old English hol (adj.) "hollow, concave;" as a noun, "hollow place; cave; orifice; perforation," from Proto-Germanic *hulan (source also of Old Saxon, Old Frisian, Old High German hol, Middle Dutch hool, Old Norse holr, German hohl "hollow," Gothic us-hulon "to hollow out"), from PIE root *kel- (1) "to cover, conceal, save." As an adjective, it has been displaced by hollow, which in Old English was only a noun, meaning "excavated habitation of certain wild animals."
As a contemptuous word for "small dingy lodging or abode" it is attested from 1610s. Meaning "a fix, scrape, mess" is from 1760. Obscene slang use for "vulva" is implied from mid-14c. Golfing hole-in-one is from 1914; as a verbal phrase from 1913. To need (something) like a hole in the head, applied to something useless or detrimental, first recorded 1944 in entertainment publications, probably a translation of a Yiddish expression such as ich darf es vi a loch in kop.