Online Etymology Dictionary

burrow (v.): c. 1600, "to place in a burrow, from burrow (n.). Figuratively (such as to burrow (one's) head) by 1862. Intransitive sense, "to bore one's way into, penetrate" is from 1610s, originally figurative (literal sense, of animals, attested by 1771). Related: Burrowed; borrowing.
burry (adj.): mid-15c., "full of burs;" see bur + -y (2).
bursa (n.): by 1788 as an English word in physiology, shortened from medieval Latin bursa mucosa "mucus pouch," from Medieval Latin bursa "bag, purse," from Late Latin bursa, variant of byrsa "hide," from Greek byrsa "hide, skin, wineskin, drum," which is of unknown origin; compare purse (n.).
bursar (n.): "treasurer of a college," 1580s, from Anglo-Latin burser "treasurer" (13c.), from Medieval Latin bursarius "purse-bearer," from bursa (see purse (n.)). Related: Bursarial.
bursary (n.): "treasury," 1690s, from Medieval Latin bursaria "treasurer's room," from bursarius (see bursar).
bursitis (n.): 1834, "inflammation of the bursa;" also see -itis.
burst (v.): Old English berstan (intransitive) "break suddenly, shatter under pressure" (class III strong verb; past tense bærst, past participle borsten), from a West Germanic metathesis of Proto-Germanic *brest- (source also of Old Saxon brestan, Old Frisian bersta, Middle Dutch berstan, Low German barsten, Dutch barsten, Old High German brestan, German bersten "to burst"), from PIE root *bhres- "to burst, break, crack."

The forms reverted to brest- in Middle English from influence of Old Norse brestan/brast/brosten, from the same Germanic root, but it was re-metathesized late 16c. and emerged in the modern form, though brast was common as past tense through 17c. and survives in dialect.

Of extended or distended surfaces from 1530s. Figuratively, in reference to being over-full of excitement, anticipation, etc., from 1630s. Transitive sense ("to cause to break") is from late 13c. Meaning "to issue suddenly and abundantly" is from c. 1300 (literal), mid-13c. (figurative). Meaning "break into sudden activity or expression" is from 1680s. Related: Bursting.
burst (n.): 1610s, "act of bursting," from burst (v.). Meaning "a spurt" (of activity, etc.) is from 1862. The earlier noun berst (early Middle English) meant "damage, injury, harm."
burthen: see burden.
bury (v.): Old English byrgan "to raise a mound, hide, bury, inter," akin to beorgan "to shelter," from Proto-Germanic *burzjan- "protection, shelter" (source also of Old Saxon bergan, Dutch bergen, Old Norse bjarga, Swedish berga, Old High German bergan "protect, shelter, conceal," German bergen, Gothic bairgan "to save, preserve"), from PIE root *bhergh- (1) "to hide, protect" (source also of Old Church Slavonic brego "I preserve, guard"). Related: Buried; burying. Burying-ground "cemetery" attested from 1711.

The Old English -y- was a short "oo" sound, like modern French -u-. Under normal circumstances it transformed into Modern English -i- (in bridge, kiss, listen, sister, etc.), but in bury and a few other words (as in merry, knell) it retained a Kentish change to "e" that took place in the late Old English period. In the West Midlands, meanwhile, the Old English -y- sound persisted, slightly modified over time, giving the standard modern pronunciation of blush, much, church.
bus (n.): 1832, abbreviation of omnibus (q.v.). The modern English noun is nothing but a Latin dative plural ending. To miss the bus, in the figurative sense of "lose an opportunity," is from 1901, Australian English (OED has a figurative miss the omnibus from 1886). Busman's holiday "leisure time spent doing what one does for a living" (1893) is probably a reference to London bus drivers riding the buses on their days off.
bus (v.): 1838, "to travel by omnibus," from bus (n.). Transitive meaning "transport students to integrate schools" is from 1961, American English. Meaning "clear tables in a restaurant" is first attested 1913, probably from the four-wheeled cart used to carry dishes. Related: Bused; busing.
busboy (n.): also bus-boy, 1913, from bus (v.) in the restaurant sense + boy.
busby (n.): "fur hat worn by hussars on parade," 1807, earlier "a kind of bushy, tall wig" (1764), of unknown origin, though it is both a place name and a surname in England. Related: Busbied.
bush (n.): "many-stemmed woody plant," Old English bysc, from West Germanic *busk "bush, thicket" (source also of Old Saxon and Old High German busc, Dutch bosch, bos, German Busch). Influenced by or combined with cognate words from Scandinavian (such as Old Norse buskr, Danish busk, but this might be from West Germanic) and Old French (busche "firewood," apparently of Frankish origin), and also perhaps Anglo-Latin bosca "firewood," from Medieval Latin busca (whence Italian bosco, Spanish bosque, French bois), which apparently also was borrowed from West Germanic; compare Boise.

In British American colonies, applied from 1650s to the uncleared districts, hence "country," as opposed to town (1780); probably originally from Dutch bosch in the same sense, because it seems to appear first in English in former Dutch colonies. Meaning "pubic hair" (especially of a woman) is from 1745. To beat the bushes (mid-15c.) is a way to rouse birds so that they fly into the net which others are holding, which originally was the same thing as beating around the bush (see beat (v.)).
bush league (adj.): "mean, petty, unprofessional," 1906, from baseball slang for the small-town baseball clubs below the minor league where talent was developed (by 1903), from bush (n.) in the slang sense of "rural, provincial," which originally was not a value judgment.
bushed (adj.): "tired," 1870, American English, perhaps from earlier sense of "lost in the woods" (1856), from bush (n.).
bushel (n.): early 14c., measure of capacity containing four pecks or eight gallons, from Old French boissel "bushel" (13c., Modern French boisseau), probably from boisse, a grain measure based on Gallo-Roman *bostia "handful," from Gaulish *bosta "palm of the hand" (compare Irish bass, Breton boz "the hollow of the hand"). The exact measure varied from place to place and according to commodity, and since late 14c. it has been used loosely to mean "a large quantity or number."
bushido (n.): 1898, from Japanese, said to mean literally "military-knight way."
bushing (n.): "metal sleeve fitted into a machine or hole," 1839, from gerundive of bush "metal lining of the axle hole of a wheel or touch hole of a gun" (1560s), from Middle Dutch busse "box" (cognate with the second element in blunderbuss).
Bushman (n.): 1785, from South African Dutch boschjesman, literally "man of the bush," from boschje, from Dutch bosje, diminutive of bosch, bos (see bush (n.)).
bushwa (n.): also bushwah, 1920, U.S. slang, euphemistic for bullshit.
bushwhacker (n.): also bush-whacker, 1809, American English, literally "one who beats the bushes" (to make his way through), perhaps modeled on Dutch bosch-wachter "forest keeper;" see bush (n.) + whack (v.). In American Civil War, "irregular who took to the woods" (1862), variously regarded as patriot guerillas or as freebooters. Hence bushwhack (v.), 1837; bushwhacking (1826).
bushy (adj.): late 14c., "overgrown with bushes," from bush (n.) + -y (2). Of hair, etc., from 1610s. Related: Bushiness.
busily (adv.): c. 1200, bisiliche; see busy (adj.) + -ly (2).
business (n.): Old English bisignes (Northumbrian) "care, anxiety, occupation," from bisig "careful, anxious, busy, occupied, diligent" (see busy (adj.)) + -ness. Middle English sense of "state of being much occupied or engaged" (mid-14c.) is obsolete, replaced by busyness.

Sense of "a person's work, occupation" is first recorded late 14c. (in late Old English bisig (adj.) appears as a noun with the sense "occupation, state of employment"). Meaning "what one is about at the moment" is from 1590s. Sense of "trade, commercial engagements" is first attested 1727. In 17c. it also could mean "sexual intercourse." Modern two-syllable pronunciation is 17c.

Business card first attested 1840; business letter from 1766. Business end "the practical or effective part" (of something) is American English, by 1874. Phrase business as usual attested from 1865. To mean business "be intent on serious action" is from 1856. To mind (one's) own business is from 1620s. Johnson's dictionary also has busiless "At leisure; without business; unemployed."
businessman (n.): 1826, from business + man (n.). Man of business is recorded from 1660s.
busk (v.): "to prepare, to dress oneself," also "to go, set out," c. 1300, probably from Old Norse buask "to prepare oneself," reflexive of bua "to prepare" (see bound (adj.2)) + contraction of Old Norse reflexive pronoun sik. Most common in northern Middle English and surviving chiefly in Scottish and northern English dialect. Related boun had the same senses in northern and Scottish Middle English. Related: Busked; busking.

The nautical term is attested from 1660s (in a general sense of "to tack, to beat to windward"), apparently from obsolete French busquer "to shift, filch, prowl," which is related to Italian buscare "to filch, prowl," Spanish buscar (from Old Spanish boscar), perhaps originally from bosco "wood" (see bush (n.)), with a hunting notion of "beating a wood" to flush game.
busk (n.): "strip of wood, whalebone, etc., used in corset-making," 1590s, probably from French busc (16c.), from Italian bosco "splinter," of Germanic origin (see bush (n.)).
busker (n.): "itinerant entertainer," 1857, from busk (v.) "to offer goods for sale only in bars and taprooms," 1851 (in Mayhew), perhaps from busk "to cruise as a pirate," which was used in a figurative sense by 1841, in reference to people living shiftless and peripatetic lives. Busker has been mistakenly derived from buskin in the stage sense.
buskin (n.): "half boot," c. 1500, origin unknown. The word exists in different forms in most of the continental languages, and the exact relationship of them all apparently has yet to be determined. The English word is perhaps immediately from Old French broissequin "buskin; a kind of cloth" (14c., Modern French brodequin by influence of broder "to embroider"), or from Middle Dutch brosekin "small leather boot," which is of uncertain origin. OED suggests a likely candidate in Spanish borcegui, earlier boszegui

Figurative senses in English relating to tragedy are from the word being used (since mid-16c.) to translate Greek kothurnus, the high, thick-soled boot worn in Athenian tragedy; contrasted with sock, the low shoe worn by comedians. Related: Buskined.
busking (n.): 1851, slang, described variously as selling articles or obscene ballads in public houses, playing music on the streets, or performing as a sort of informal stand-up comedy act in pubs, perhaps from an earlier word meaning "to cruise as a pirate" (see busker).
buss (n.): "a kiss," 1560s; probably of imitative origin, as are Welsh and Gaelic bus "kiss, lip," French baiser "kiss" (12c., from Latin basiare), Spanish buz, German dialectal Buss.
buss (v.): 1570s, from buss (n.). Related: Bussed; bussing.
Kissing and bussing differ both in this,
We busse our wantons, but our wives we kisse.

[Robert Herrick, "Hesperides," 1648]
bussing (n.): "kissing," 1888, verbal noun from buss (v.).
bust (n.1): 1690s, "sculpture of upper torso and head," from French buste (16c.), from Italian busto "upper body," from Latin bustum "funeral monument, tomb," originally "funeral pyre, place where corpses are burned," perhaps shortened from ambustum, neuter of ambustus "burned around," past participle of amburere "burn around, scorch," from ambi- "around" + urere "to burn." Or perhaps from Old Latin boro, the early form of classical Latin uro "to burn." Sense development in Italian is probably from Etruscan custom of keeping dead person's ashes in an urn shaped like the person when alive. Meaning "bosom" is by 1884.
bust (n.2): variant of burst (n.), 1764, American English. For loss of -r-, compare ass (n.2). Originally "frolic, spree;" sense of "sudden failure" is from 1842. Meaning "police raid or arrest" is from 1938. Phrase ______ or bust as an emphatic expression attested by 1851 in British depictions of Western U.S. dialect. Probably from earlier expression bust (one's) boiler, by late 1840s, a reference to steamboat boilers exploding when driven too hard.
bust (v.): "to burst," 1806, variant of burst (v.); for loss of -r-, compare ass (n.2). Meaning "go bankrupt" is from 1834. Meaning "break into" is from 1859. The slang meaning "demote" (especially in a military sense) is from 1918; that of "place under arrest" is from 1953 (earlier "to raid" from Prohibition). In card games, "to go over a score of 21," from 1939. Related: Busted; busting.
bustard (n.): large crane-like bird, mid-15c. (late 14c. as a surname), from Old French bistarde, said to be from Latin avis tarda, but the sense of this ("slow bird") is the opposite of the bird's behavior.
busted (adj.): "broken, ruined," 1837, past participle adjective from bust (v.).
buster (n.): 1838, "anything large; a man of great strength," American English slang (originally Missouri/Arkansas), perhaps meaning something that takes one's breath away and an agent noun from bust (v.). Around the same years, buster (as an extended form of bust (n.)) also meant "a frolic, a spree." Hence "a roistering blade" (OED; probably not the favored definition in old Missouri and Arkansas), attested from 1850. As a generic or playful address to a male, from 1948, American English. Meaning "horse-breaker" is from 1891, American English; hence back-formed verb bust (v.) "break a horse."
bustier (n.): 1979, from French bustier, from buste "bust" (see bust (n.1)).
bustle (v.): "be active," 1570s (bustling "noisy or excited activity" is from early 15c.), frequentative of Middle English bresten "to rush, break," from Old English bersten (see burst (v.)), influenced by Old Norse buask "to make oneself ready" (see busk (v.)), or it might be from busk (v.) via a frequentative form buskle. Related: Bustled; bustling; bustler.
bustle (n.2): "padding in a skirt," 1788, of uncertain origin, perhaps from German Buschel "bunch, pad," or it might be a special use of bustle (n.1) with reference to "rustling motion."
BUSTLE. A pad stuffed with cotton, feathers, bran, &c., worn by ladies for the double purpose of giving a greater rotundity or prominence to the hips, and setting off the smallness of the waist. [Bartlett, "Dictionary of Americanisms," 1848]
bustle (n.1): "activity, stir, fuss, commotion," 1630s, from bustle (v.).
bustling (adj.): of a place, 1880, present participle adjective from bustle (v.).
busty (adj.): "having large breasts," 1944, from bust (n.1) in the "bosom" sense + -y (2). Related: Bustiness.
busy (adj.): Old English bisig "careful, anxious," later "continually employed or occupied," cognate with Old Dutch bezich, Low German besig; no known connection with any other Germanic or Indo-European language. Still pronounced as in Middle English, but for some unclear reason the spelling shifted to -u- in 15c.

The notion of "anxiousness" has drained from the word since Middle English. Often in a bad sense in early Modern English, "prying, meddlesome" (preserved in busybody). The word was a euphemism for "sexually active" in 17c. Of telephone lines, 1893. Of display work, "excessively detailed, visually cluttered," 1903.
busy (v.): late Old English bisgian, from busy (adj.). Related: Busied; busying.
busy-work (n.): also busy work, 1910, from busy (adj.) + work (n.).