bump (v.)youdaoicibaDictYouDict[bump 词源字典]
1560s, "to bulge out;" 1610s, "to strike heavily," perhaps from Scandinavian, probably echoic, original sense was "hitting" then of "swelling from being hit." Also has a long association with obsolete bum "to make a booming noise," which perhaps influenced surviving senses such as bumper crop, for something full to the brim (see bumper). To bump into "meet" is from 1880s; to bump off "kill" is 1908 in underworld slang. Related: Bumped; bumping. Bumpsy (adj.) was old slang for "drunk" (1610s).[bump etymology, bump origin, 英语词源]
bumper (n.)youdaoicibaDictYouDict
1670s, "glass filled to the brim;" perhaps from notion of bumping as "large," or from a related sense of "booming" (see bump (v.)). Meaning "anything unusually large" is from 1759, slang. Agent-noun meaning "buffer of a car" is from 1839, American English, originally in reference to railway cars; 1901 of automobiles (in phrase bumper-to-bumper, in reference to a hypothetical situation; of actual traffic jams by 1908).
bumpkin (n.)youdaoicibaDictYouDict
"awkward country fellow," 1560s, probably from Middle Dutch bommekijn "little barrel," diminutive of boom "tree" (see beam (n.)). Apparently, though itself Dutch, it began as a derogatory reference to Dutch people as short and dumpy.
bumptious (adj.)youdaoicibaDictYouDict
"assertive," 1803, probably a humorous coinage from bump on the pattern of fractious, etc. Related: Bumptiously; bumptiousness.
bumpy (adj.)youdaoicibaDictYouDict
1865, from bump + -y (2).
Fasten your seatbelts. It's going to be a bumpy night. [Bette Davis ("Margo Channing"), "All About Eve," 1950]
Related: Bumpiness.
bun (n.)youdaoicibaDictYouDict
late 14c., origin obscure, perhaps from Old French buignete "a fritter," originally "boil, swelling," diminutive of buigne "swelling from a blow, bump on the head," from a Germanic source (compare Middle High German bunge "clod, lump"), or from Gaulish *bunia (compare Gaelic bonnach). Spanish buñelo "a fritter" apparently is from the same source. Of hair coiled at the back of the head, first attested 1894. To have a bun in the oven "be pregnant" is from 1951.

The first record of buns in the sense of "male buttocks" is from 1960s, perhaps from a perceived similarity; but bun also meant "tail of a hare" (1530s) in Scottish and northern England dialect and was transferred to human beings (and conveniently rhymed with nun in ribald ballads). This may be an entirely different word; OED points to Gaelic bun "stump, root."
buna (n.)youdaoicibaDictYouDict
synthetic rubber made from butadiene, from German Buna, from first elements of butadiene, name of a hydrocarbon (related to butane; the suffix indicates the presence of two double bonds) + Na, indicating sodium (from natrium; see sodium).
bunch (n.)youdaoicibaDictYouDict
early 14c., "protuberance on the body, swelling," perhaps echoic of the sound of hitting and connected to bump (compare, possibly in similar relationship, hump/hunch).

The sense of "cluster" is mid-15c.; connection with the earlier sense is obscure, and this may be a separate word, perhaps through a nasalized form of Old French bouge (2), 15c., from Flemish boudje diminutive of boud "bundle." Meaning "a lot, a group" is from 1620s.
bunch (v.)youdaoicibaDictYouDict
"to bulge out," late 14c., from bunch (n.). Meaning "to gather up in a bunch" (transitive) is from 1828; sense of "to crowd together" (intransitive) is from 1873. Related: Bunched; bunching.
buncombe (n.)youdaoicibaDictYouDict
see bunk (n.2).
bund (n.)youdaoicibaDictYouDict
"league, confederacy," 1850, from German Bund (related to English band (n.2) and bind (v.)). In names of various fraternal organizations, in U.S. especially the German-American Bund, pro-Nazi organization founded 1936.
Bundestag (n.)youdaoicibaDictYouDict
German federal council, 1879, from German Bundestag, from genitive of Bund "league, confederacy, association" (related to English band (n.2) and bind (v.)) + tag, literally "day;" as a verb, tagen, meaning "to sit in conference" (see day; also compare adjourn). Hence also Bundesrat, from rat, rath "council" (see read (v.)).
bundle (n.)youdaoicibaDictYouDict
early 14c., "bound collection of things," from Middle Dutch bondel, diminutive of bond, from binden "to bind," or perhaps a merger of this word and Old English byndele "binding," from Proto-Germanic *bundilin (source also of German bündel "to bundle"), from PIE root *bhendh- "tie" (see bend (v.)). Meaning "a lot of money" is from 1899. To be a bundle of nerves "very anxious" is from 1938.
bundle (v.)youdaoicibaDictYouDict
1620s, "to make into a bundle," from bundle (n.); meaning "to wrap up in warm heavy clothes" is from 1893. Meaning "to sleep with another, clothed, in the same bed," a noted former custom in New England, is from 1781. Meaning "to send away hurriedly" is from 1823. Related: Bundled; bundling.
bundling (n.)youdaoicibaDictYouDict
1640s, "a gathering into a bundle," verbal noun from bundle (v.). Meaning "sharing a bed for the night, fully dressed, wrapped up with someone of the opposite sex" (1782) is a former local custom in New England (especially Connecticut and southeastern Massachusetts). It was noted there from about 1750s and often regarded by outsiders as grossly immoral, but New Englanders wrote defenses of it and claimed it was practiced elsewhere, too. It seems to have died out with the 18th century.
I am no advocate for temptation; yet must say, that bundling has prevailed 160 years in New England, and, I verily believe, with ten times more chastity than the sitting on a sofa. I had daughters, and speak from near forty years' experience. Bundling takes place only in cold seasons of the year--the sofa in summer is more dangerous than the bed in winter. [The Rev. Samuel Peters, "A general history of Connecticut," 1782]
bung (n.)youdaoicibaDictYouDict
mid-15c., "large stopper for a cask," 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." Transferred to the cask-mouth itself (also bung-hole) from 1570s.
bung-hole (n.)youdaoicibaDictYouDict
also bunghole, "hole in a cask for a stopper," 1570s, from bung (n.) + hole (n.). Sense extended to "anus" by c. 1600.
bungalow (n.)youdaoicibaDictYouDict
1670s, from Gujarati bangalo, from Hindi bangla "low, thatched house," literally "Bengalese," used elliptically for "house in the Bengal style" (see Bengal). Related: Bungaloid.
bungee (n.)youdaoicibaDictYouDict
1930, "elastic rope;" used in late 19c. British schoolboy slang for "rubber eraser;" probably from notions of bouncy and spongy; first record of bungee jumping is from 1979.
bungle (v.)youdaoicibaDictYouDict
1520s, origin obscure. OED suggests imitative; perhaps a mix of boggle and bumble, or more likely from a Scandinavian word akin to Swedish bangla "to work ineffectually," Old Swedish bunga "to strike" (related to German Bengel "cudgel," also "rude fellow"). Related: Bungled; bungling.