Online Etymology Dictionary

bobcat (n.): North American lynx, 1873, in a Maine context; so called for its short tail; see bob (n.2) + cat (n.).
bobolink (n.): American passerine bird, 1796, American English, earlier bob-lincoln, bob-o-Lincoln (1774), imitative of the hearty song of the bird.
bobsled (n.): 1839, from bob (n.2) + sled (n.). So called because it is a short type.
bobwhite (n.): North American partridge, 1819, so called from the sound of its cry.
Boccaccio: the name means "big-mouth" in Italian, from boccaccia, augmentative of bocca "mouth" (see bouche).
bocce (n.): from Italian bocce "(wooden) balls," plural of boccia, which is related to French bosse "bump, hump," perhaps from a Germanic source.
Boche (n.): "German soldier in World War I," 1914, perhaps from French slang boche "rascal," applied to the Germans; a word of unknown origin. Another theory traces it to French Allemand "German," in eastern French Al(le)moche, altered contemptuously to Alboche by association with caboche, a slang word for "head," literally "cabbage" (compare tete de boche, French for "German" in an 1887 slang dictionary). All the French terms are no older than mid-19c.
bock (n.): strong, dark type of German beer, 1856, from German ambock, from Bavarian dialectal pronunciation of Einbecker bier, from Einbeck, Hanover, where it was first brewed; popularly associated with Bock "a goat." Brewed in December and January, drunk in May.
bod (n.): 1788, "a person," short for body. Meaning "physical body" is recorded from 1933.
bodacious (adj.): 1837 (implied in bodaciously), Southern U.S. slang, perhaps from bodyaciously "bodily, totally," or a blend of bold and audacious, which suits the earliest attested sense of the word. Popularized anew by 1982 Hollywood film "An Officer and a Gentleman."
bode (v.): Old English bodian "proclaim, announce; foretell," from boda "messenger," probably from Proto-Germanic *budon- (source also of Old Saxon gibod, German gebot, Old Norse boð), from PIE *bheudh- "be aware, make aware" (source also of Sanskrit bodhati "is awake, is watchful, observes," buddhah "awakened, enlightened;" Old Church Slavonic bljudo "to observe;" Lithuanian budeti "to be awake;" Old Irish buide "contentment, thanks"). As a shortened form of forebode (usually evil), it dates from 1740. Related: Boded; boding.
bodega (n.): 1848, from Mexican Spanish, from Spanish bodega "a wine shop; cellar," from Latin apotheca, from Greek apotheke "depot, store" (see apothecary). The same word as boutique.
Bodhisattva (n.): 1828, from Sanskrit, literally "one whose essence is perfect knowledge," from bodhi "perfect knowledge" (see Buddha) + sattva "reality, being."
bodice (n.): 1560s, oddly spelled plural of body, name of a tight-fitting Elizabethan garment covering the torso; plural because the body came in two parts which fastened in the middle. Bodice-ripper for "racy romance novel" is from 1981.
bodily (adj.): c. 1300, "pertaining to the body;" also opposed to "spiritual;" from body + -ly (1). As an adverb (with -ly (2)) from late 14c.
bodkin (n.): late 14c., boydekin, of unknown origin. The ending suggests a diminutive formation, and Celtic has been suggested as the source of the root.
Bodleian: from Sir Thomas Bodley (1545-1613), who in 1597 refounded the library at Oxford University.
Bodoni: 1880, typeface based on that used by celebrated Italian printer Giambattista Bodoni (1740-1813) of Parma. The modern type of this name is a composite of his many forms.
body (n.): Old English bodig "trunk, chest" (of a man or animal); related to Old High German botah, of unknown origin. Not elsewhere in Germanic, and the word has died out in German (replaced by leib, originally "life," and körper, from Latin). In English, extension to "person" is from late 13c. Meaning "main part" of anything was in late Old English, hence its use in reference to vehicles (1520s).

Contrasted with soul since at least mid-13c. Meaning "corpse" (short for dead body) is from late 13c. Transferred to matter generally in Middle English (as in heavenly body, late 14c.). Body politic "the nation, the state" first recorded 1520s, legalese, with French word order. Body image was coined 1935. Body language is attested from 1967, perhaps from French langage corporel (1966). Phrase over my dead body attested by 1833.
bodyguard (n.): 1735, "retinue, escort," collective singular, from body + guard (n.). Attested 1861 as "a soldier of the bodyguard."
Boeing: U.S. aerospace corporation, founded 1916 by William E. Boeing in Seattle, Washington, as an airplane manufacturer. The family name is German.
Boeotian (adj.): 1590s, "ignorant, dull," from Boeotia, district around Thebes in ancient Greece (said to have been so called for its cattle pastures; Greek bous = "ox"), whose inhabitants were characterized as proverbially dull and countrified by their neighbors, the Athenians. The Boeotians presumably held reciprocal opinions, but their great writers, Plutarch and Pindar, though patriots, are full of praise for Athenian deeds and institutions.
Though his aim was to vindicate Boeotia, [Pindar] has probably done her a disservice, in that he has helped to immortalise the scurrilous proverb Βοιωτία ύς, which he wished to confute. ... If left to itself, the slander might have passed into oblivion long ago. [W. Rhys Roberts, "The Ancient Boeotians," 1895]
Boer (n.): "Dutch colonist in South Africa," 1824, from Dutch boer "farmer," from Middle Dutch, cognate with Old English gebur "dweller, farmer, peasant," and thus related to bower, German Bauer, and the final syllable of neighbor (see boor). Boer War (1899-1902) was technically the Second Boer War, there having been a brief preview 1880-1881.
boffin (n.): "person engaged in innovative research," especially in aviation, 1945; earlier "elderly naval officer" (1941), probably from one of the "Mr. Boffins" of English literature (as in "Our Mutual Friend").
boffo (adj.): strikingly successful, by 1961, show biz slang, probably echoic of a "hit."
bog (n.): c. 1500, from Gaelic and Irish bogach "bog," from adjective bog "soft, moist," from PIE *bhugh-, from root *bheugh- "to bend" (see bow (v.)). Bog-trotter applied to the wild Irish from 1670s.
bog (v.): "to sink (something or someone) in a bog," c. 1600, from bog (n.). Intransitive use from c. 1800. Related: Bogged; bogging.
bogart (v.): 1969, "to keep a joint in your mouth," dangling from the lip like Humphrey Bogart's cigarette in the old movies, instead of passing it on. First attested in "Easy Rider." The word was also used 1960s with notions of "get something by intimidation, be a tough guy" (again with reference to the actor and the characters he typically played). In old drinking slang, Captain Cork was "a man slow in passing the bottle."
bogey (n.1): World War II aviator slang for "unidentified aircraft, presumably hostile," probably ultimately from bogge, a variant of Middle English bugge "a frightening specter" (see bug (n.)). Thus it shares ancestry with many dialect words, such as bog/bogge (attested 16c.-17c.), bogeyman (16c.), boggart "specter that haunts a gloomy spot" (c. 1570, in Westmoreland, Lancashire, Cheshire, and Yorkshire). The earliest modern form appears to be Scottish bogle "ghost," attested from c. 1500 and popularized c. 1800 in English literature by Scott, Burns, etc.
bogey (n.2): in golfing, c. 1891, originally "number of strokes a good player is supposed to need for a given hole or course;" later, "score one over par" (1946); from the same source as bogey (n.1), on the notion of a "phantom" opponent, represented by the "ground score." The word was in vogue at the time in Britain because of the popularity of a music hall tune "Hush, Hush, Hush, Here Comes the Bogey Man."
One popular song at least has left its permanent effect on the game of golf. That song is 'The Bogey Man.' In 1890 Dr. Thos. Browne, R.N., the hon. secretary of the Great Yarmouth Club, was playing against a Major Wellman, the match being against the 'ground score,' which was the name given to the scratch value of each hole. The system of playing against the 'ground score' was new to Major Wellman, and he exclaimed, thinking of the song of the moment, that his mysterious and well-nigh invincible opponent was a regular 'bogey-man.' The name 'caught on' at Great Yarmouth, and to-day 'Bogey' is one of the most feared opponents on all the courses that acknowledge him. [1908, cited in OED]
Other early golfing sources give it an American origin. As a verb, attested by 1948.
bogeyman (n.): 16c.; see bogey (n.1) + man (n.).
boggle (v.): 1590s, "to start with fright (as a startled horse does), shy, take alarm," from Middle English bugge "specter" (among other things, supposed to scare horses at night); see bug (n.); also compare bogey (n.1). The meaning "to raise scruples, hesitate" is from 1630s. As a noun from 1650s. Related: Boggled; boggling; boggler (from c. 1600 as "one who hesitates").
boggy (adj.): 1580s, from bog (n.) + -y (2). Related: Bogginess.
bogus: 1838, "counterfeit money, spurious coin," American English, apparently from a slang word applied (according to some sources first in Ohio in 1827) to a counterfeiter's apparatus.
One bogus or machine impressing dies on the coin, with a number of dies, engraving tools, bank bill paper, spurious coin, &c. &c. making in all a large wagon load, was taken into possession by the attorney general of Lower Canada. [Niles' Register, Sept. 7, 1833, quoting from Concord, New Hampshire, "Statesman," Aug. 24]
Some trace this to tantrabobus, also tantrabogus, a late 18c. colloquial Vermont word for any odd-looking object, in later 19c. use "the devil," which might be connected to tantarabobs, recorded as a Devonshire name for the devil. Others trace it to the same source as bogey (n.1).
boh (interj.): see boo.
Bohemia: central European kingdom, mid-15c., Beeme, from Middle French Boheme "Bohemia," from Latin Boiohaemum (Tacitus), from Boii, the Celtic people who settled in what is now Bohemia (and were driven from it by the Germanic Marcomans early 1c.; singular Boius, fem. Boia, perhaps literally "warriors") + Proto-Germanic *haimaz "home" (see home (n.)). Attested from 1861 in meaning "community of artists and social Bohemians" or in reference to the district where they live (see bohemian).
bohemian (n.): "a gypsy of society," 1848, from French bohemién (1550s), from the country name (see Bohemia). The modern sense is perhaps from the use of this country name since 15c. in French for "gypsy" (they were wrongly believed to have come from there, though their first appearance in Western Europe may have been directly from there), or from association with 15c. Bohemian heretics. It was popularized by Henri Murger's 1845 story collection "Scenes de la Vie de Boheme," the basis of Puccini's "La Bohème." Used in English 1848 in Thackary's "Vanity Fair."
The term 'Bohemian' has come to be very commonly accepted in our day as the description of a certain kind of literary gipsey, no matter in what language he speaks, or what city he inhabits .... A Bohemian is simply an artist or littérateur who, consciously or unconsciously, secedes from conventionality in life and in art. ["Westminster Review," 1862]
Bohunk (n.): 1903, U.S. derogatory slang for "lower class immigrant from Central or Eastern Europe," probably from Bohemian + a distortion of Hungarian.
boil (v.): early 13c., from Old French bolir "boil, bubble up, ferment, gush" (12c., Modern French bouillir), from Latin bullire "to bubble, seethe," from PIE base *beu- "to swell" (see bull (n.2)). The native word is seethe. Figurative sense of "to agitate the feelings" is from 1640s.
I am impatient, and my blood boyls high. [Thomas Otway, "Alcibiades," 1675]
Related: Boiled; boiling. Boiling point is recorded from 1773.
boil (n.): "hard tumor," altered from Middle English bile (Kentish bele), perhaps by association with the verb; from Old English byl, byle "boil, carbuncle," from West Germanic *buljon- "swelling" (source also of Old Frisian bele, Old High German bulia, German Beule). Perhaps ultimately from PIE root *bhel- (2) "to swell" (see bole), or from *beu- "to grow, swell" (see bull (n.2); also compare boast (n.)). Compare Old Irish bolach "pustule," Gothic ufbauljan "to puff up," Icelandic beyla "hump."
boiler (n.): 1540s, agent noun from boil (v.). Meaning "vessel for boiling" is from 1725; steam engine sense is from 1757.
boilermaker (n.): "a maker of boilers for engines," 1814, from boiler (n.) + maker. Meaning "shot of whiskey with a glass of beer" is short for boilermaker's delight (1910), strong cheap whiskey, so called in jest from the notion that it would clean the scales from the interior of a boiler.
boilerplate (n.): newspaper (and now information technology) slang for "unit of writing that can be used over and over without change," 1893, from a literal meaning (1840) "metal rolled in large, flat plates for use in making steam boilers." The connecting notion is probably of sturdiness or reusability. From 1890s to 1950s, publicity items were cast or stamped in metal ready for the printing press and distributed to newspapers as filler. The largest supplier was Western Newspaper Union.
boink: "have sex with" (v.); "the sex act" (n.), slang by c. 2000, perhaps an alteration of bonk in its popular sexual sense. Related: Boinked; boinking.
Boise: city in Idaho, U.S., from French-Canadian boisé, literally "wooded," from French bois "wood," which (with Italian bosco, Spanish bosque, Medieval Latin boscus) apparently is borrowed from the Germanic root of bush (n.). Medieval Latin boscus was used especially of "woodland pasture."
boisterous (adj.): late 15c., unexplained alteration of Middle English boistous (c. 1300) "rough, coarse (as of food), clumsy, violent," which is of unknown origin, perhaps from Anglo-French bustous "rough (road)," which is perhaps from Old French boisteos "curved, lame; uneven, rough" (Modern French boiteux), itself of obscure origin. Another guess traces it via Celtic to Latin bestia. Used of persons from 1560s. Related: Boisterously; boisterousness.
bok choy (n.): type of Chinese cabbage, from Cantonese, literally "white vegetable."
bold (adj.): Old English beald (West Saxon), bald (Anglian) "bold, brave, confident, strong," from Proto-Germanic *balthaz (source also of Old High German bald "bold, swift," in names such as Archibald, Leopold, Theobald; Gothic balþei "boldness;" Old Norse ballr "frightful, dangerous"), perhaps from PIE *bhol-to- suffixed form of *bhel- (2) "to blow, swell" (see bole).

Of flavors (coffee, etc.) from 1829. The noun meaning "those who are bold" is from c. 1300. Old French and Provençal baut "bold," Italian baldo "bold, daring, fearless" are Germanic loan-words.
bold-face (n.): in typography, 1845, from bold (adj.) + face (n.). In reference to types, bold (adj.) is attested from 1790, perhaps from the secondary sense "easily visible, striking to the eye."
bole (n.): early 14c., from Old Norse bolr "tree trunk," from Proto-Germanic *bulas (source also of Middle Dutch bolle "trunk of a tree"), from PIE *bhel- (2) "to blow, inflate, swell" (source also of Greek phyllon "leaf," phallos "swollen penis;" Latin flos "flower," florere "to blossom, flourish," folium "leaf;" Old Prussian balsinis "cushion;" Old Norse belgr "bag, bellows;" Old English bolla "pot, cup, bowl;" Old Irish bolgaim "I swell," blath "blossom, flower," bolach "pimple," bolg "bag;" Breton bolc'h "flax pod;" Serbian buljiti "to stare, be bug-eyed;" Serbo-Croatian blazina "pillow").