Online Etymology Dictionary

bird-brain (n.): also birdbrain, 1936, slang, "stupid person," also perhaps suggestive of flightiness, from bird (n.1) + brain (n.).
birdbath (n.): also bird-bath, bird bath, 1862, from bird (n.1) + bath (n.).
birdcage (n.): also bird-cage, late 15c., from bird (n.1) + cage (n.).
birdie (n.): "little bird," 1792, from bird (n.1) + -ie. As golf slang for "a hole played one under par," by 1908, perhaps from bird (n.) in American English slang sense of "exceptionally clever or accomplished person or thing" (1839).
birdlime (n.): viscous sticky stuff prepared from holly bark and used to catch small birds, mid-15c., from bird (n.1) + lime (n.1). Used as rhyming slang for time (especially time in prison) by 1857.
birdseed (n.): 1736, from bird (n.1) + seed (n.).
biretta (n.): square cap worn by Catholic clergy, 1590s, from Italian beretta, from Late Latin birrus, birrum "large cloak with hood;" perhaps of Gaulish origin, or from Greek pyrros "flame-colored, yellow."
Birmingham: industrial city in central England, 1086, Bermingehame, literally "homestead of the place (or people) named for Beorma, some forgotten Anglo-Saxon person, whose name probably is a shortening of Beornmund. The Birmingham in Alabama, U.S., was founded 1871 as an industrial center and named for the English city.
Biro (n.): proprietary name of a type of ball-point pen, 1947, from László Bíró, the Hungarian inventor. The surname means "judge."
birth (n.): early 13c., from a Scandinavian source, cf. Old Norse *byrðr (replacing cognate Old English gebyrd "birth, descent, race; offspring; nature; fate"), from Proto-Germanic *gaburthis (cf. Old Frisian berd, Old Saxon giburd, Dutch geboorte, Old High German giburt, German geburt, Gothic gabaurþs), from PIE *bhrto past participle of root *bher- (1) "to carry; to bear children" (cf. Sanskrit bhrtih "a bringing, maintenance," Latin fors, genitive fortis "chance;" see bear (v.)). Suffix -th is for "process" (as in bath, death). Meaning "parentage, lineage, extraction" (revived from Old English) is from mid-13c. Birth control is from 1914; birth rate from 1859. Birth certificate is from 1842.
birth (v.): mid-13c., from birth (n.). Related: Birthed; birthing.
birthday (n.): late 14c., from Old English byrddæg, "anniversary celebration of someone's birth" (at first usually a king or saint); see birth (n.) + day. Meaning "day on which one is born" is from 1570s. Birthnight is attested from 1620s.
birthday suit (n.): first attested 1730s, but probably much older. The notion is the suit of clothes one was born in, i.e., no clothes at all. Cf. Middle English mother naked "naked as the day one was born;" Middle Dutch moeder naect, German mutternackt.
birthmark (n.): also birth-mark, by 1805, from birth (n.) + mark (n.1). Birth marks in 17c. could be longing marks; supposedly they showed the image of something longed for by the mother while expecting. Related: Birthmarked.
birthplace (n.): also birth-place, c.1600, from birth (n.) + place (n.).
birthright (n.): also birth-right, 1530s, from birth (n.) + right (n.). Used as an adjective from 1650s, especially by Quakers.
birthstone (n.): 1874, from birth (n.) + stone (n.).
bis-: word-forming element meaning "twice," from Latin bis "twice, in two ways, doubly," from Old Latin dvis, cognate with Sanskrit dvih, Avestan bish, Greek dis, Middle High German zwis "twice," from PIE *dwo- "two" (see two). Also the form of bi- used before -s-, -c-, or a vowel.
biscotti (n.): 1990s, from Italian biscotti, plural of biscotto, from Old Italian biscotto, from Medieval Latin biscoctum (see biscuit).
biscuit (n.): respelled early 19c. from bisket (16c.), ultimately (besquite, early 14c.) from Old French bescuit (12c.), literally "twice cooked;" altered under influence of cognate Old Italian biscotto, both from Medieval Latin biscoctum, from Latin (panis) bis coctus "(bread) twice-baked;" see bis- + cook (v.). U.S. sense of "soft bun" is recorded from 1818.
bisect (v.): "to cut in two," 1640s, from Modern Latin bisectus, from Latin bi- "two" (see bi-) + secare "to cut" (see section (n.)). Related: Bisected; bisecting.
bisection (n.): "division in two," 1650s, noun of state from bisect. Related: Bisectional.
bisector (n.): 1821; agent noun from bisect.
bisexual (adj.): 1824, "having both sexes in one being, hermaphroditic," from bi- + sexual. Meaning "attracted to both sexes" is from 1914; the noun in this sense is attested from 1922. Not in general use until 1950s. Noun is recorded from 1922. Ambisexual was suggested 1924 in this sense but never caught on.
bisexuality (n.): "attraction to both sexes" 1892, in translation of Krafft-Ebing; see bisexual + -ity.
bishop (n.): Old English bisceop "bishop, high priest (Jewish or pagan)," from Late Latin episcopus, from Greek episkopos "watcher, overseer," a title for various government officials, later taken over in a Church sense, from epi- "over" (see epi-) + skopos "watcher," from skeptesthai "look at" (see scope (n.1)). Given a specific sense in the Church, but the word also was used in the New Testament as a descriptive title for elders, and continues as such in some non-hierarchical Christian sects.
A curious example of word-change, as effected by the genius of different tongues, is furnished by the English bishop and the French évêque. Both are from the same root, furnishing, perhaps the only example of two words from a common stem so modifying themselves in historical times as not to have a letter in common. (Of course many words from a far off Aryan stem are in the same condition.) The English strikes off the initial and terminal syllables, leaving only piscop, which the Saxon preference for the softer labial and hissing sounds modified into bishop. Évêque (formerly evesque) merely softens the p into v and drops the last syllable. [William S. Walsh, "Handy-Book of Literary Curiosities," Philadelphia, J.B. Lippincott, 1892]
Late Latin episcopus in Spanish became obispo. Cognate with Old Saxon biscop, Old High German biscof. The chess piece (formerly archer, before that alfin) was so called from 1560s.
bishopric (n.): Old English bisceoprice "diocese, province of a bishop," from bishop + rice "realm, dominion, province" (see regal).
Bismarck: "drink of champagne and stout" (also called a black velvet), 1910, named for the German chancellor (1815-1898), who was said to have been fond of it. The surname is said to be short for Biscofsmark "bishop's boundary."
bismillah: first attested in English in Byron, from Arabic bi'smillah(i) "in the name of God" (Allah).
bismuth (n.): 1660s, from obsolete German Bismuth, also Wismut, Wissmuth (early 17c.), of unknown origin; perhaps a miner's contraction of wis mat "white mass," from Old High German hwiz "white." Latinized 1530 by Georgius Agricola (who may have been the first to recognize it as an element) as bisemutum. According to Klein, not from Arabic.
bison (n.): c.1600, from French bison (15c.), from Latin bison "wild ox," borrowed from Proto-Germanic *wisand- "aurochs" (cf. Old Norse visundr, Old High German wisunt "bison," Old English/Middle English wesend, which is not attested after c.1400). Possibly ultimately of Baltic or Slavic origin, and meaning "the stinking animal," in reference to its scent while rutting (see weasel). A European wild ox formerly widespread on the continent, including the British Isles, now surviving on forest reserves in Lithuania. Applied 1690s to the North American species commonly mis-called a buffalo.
bisque (n.1): soup, 1640s, bisk, from French bisque "crayfish soup" (17c.), said to be an altered form of Biscaye "Biscay." Gamillscheg says: "Volkstümliche Entlehnung aus norm. bisque 'schlechtes Getränk.'" Modern form in English from 1731.
bisque (n.2): "unglazed porcelain," 1660s, alteration of biscuit.
bissextile: 1580s (n.); 1590s (adj.), in reference to Roman leap year, from Late Latin (annus) bissextilis "leap year," literally "the twice sixth-day," because the sixth day before the Calends of March was doubled.
bistro (n.): 1906, from French bistro (1884), originally Parisian slang for "little wineshop or restaurant," of unknown origin. Commonly said to be from Russian bee-stra "quickly," picked up during the Allied occupation of Paris in 1815 after the defeat of Napoleon; but this, however quaint, is unlikely. Another guess is that it is from bistraud "a little shepherd," a word of the Poitou dialect, from biste "goat."
bit (n.1): "small piece," c.1200; related Old English bite "act of biting," and bita "piece bitten off," probably are the source of the modern words meaning "boring-piece of a drill" (1590s), "mouthpiece of a horse's bridle" (mid-14c.), and "a piece bitten off, morsel" (c.1000). All from Proto-Germanic *biton (cf. Old Saxon biti, Old Norse bit, Old Frisian bite, Middle Dutch bete, Old High German bizzo "biting," German Bissen "a bite, morsel"), from PIE root *bheid- "to split" (see fissure).

Meaning "small piece, fragment" is from c.1600. Sense of "short space of time" is 1650s. Theatrical bit part is from 1909. Money sense in two bits, etc. is originally from Southern U.S. and West Indies, in reference to silver wedges cut or stamped from Spanish dollars (later Mexican reals); transferred to "eighth of a dollar."
bit (n.2): computerese word, 1948 abbreviation coined by U.S. computer pioneer John W. Tukey (1915-2000) of binary digit, probably chosen for its identity with bit (n.1).
bit (v.): past tense of bite.
bitch (n.): Old English bicce "female dog," probably from Old Norse bikkjuna "female of the dog" (also fox, wolf, and occasionally other beasts), of unknown origin. Grimm derives the Old Norse word from Lapp pittja, but OED notes that "the converse is equally possible." As a term of contempt applied to women, it dates from c.1400; of a man, c.1500, playfully, in the sense of "dog." Used among male homosexuals from 1930s. In modern (1990s, originally black English) slang, its use with reference to a man is sexually contemptuous, from the "woman" insult.
BITCH. A she dog, or doggess; the most offensive appellation that can be given to an English woman, even more provoking than that of whore. ["Dictionary of the Vulgar Tongue," 1811]
Bitch goddess coined 1906 by William James; the original one was success.
bitch (v.): "to complain," attested at least from 1930, perhaps from the sense in bitchy, perhaps influenced by the verb meaning "to bungle, spoil," which is recorded from 1823. But bitched in this sense seems to echo Middle English bicched "cursed, bad," a general term of opprobrium (e.g. Chaucer's bicched bones "unlucky dice"), which despite the hesitation of OED, seems to be a derivative of bitch (n.).
bitching (adj.): also bitchen, "good," teen/surfer slang attested from 1950s, apparently from bitch (v.) in some inverted sense. Meaning "complaining" is by 1945, U.S. armed services.
bitchy (adj.): 1925, U.S. slang, "sexually provocative;" later (1930s) "spiteful, catty, bad-tempered" (usually of females); from bitch + -y (2). Earlier in reference to male dogs though to look less rough or coarse than usual.
Mr. Ramsay says we would now call the old dogs "bitchy" in face. That is because the Englishmen have gone in for the wrong sort of forefaces in their dogs, beginning with the days when Meersbrook Bristles and his type swept the judges off their feet and whiskers and an exaggerated face were called for in other varieties of terriers besides the wire haired fox. [James Watson, "The Dog Book," New York, 1906]
Related: Bitchily; bitchiness.
bite (v.): Old English bitan (class I strong verb; past tense bat, past participle biten), from Proto-Germanic *bitan (cf. Old Saxon bitan, Old Norse and Old Frisian bita, Middle Dutch biten, Dutch bijten, German beissen, Gothic beitan "to bite"), from PIE root *bheid- "to split, crack" (see fissure).

To bite the bullet is said to be 1700s military slang, from old medical custom of having the patient bite a lead bullet during an operation to divert attention from pain and reduce screaming. Figurative use from 1891; the custom itself attested from 1840s. To bite (one's) tongue "refrain from speaking" is 1590s. To bite the dust "die" is 1750 (Latin had the same image; cf. Virgil: procubuit moriens et humum semel ore momordit). To bite off more than one can chew (c.1880) is U.S. slang, from plug tobacco.
bite (n.): c.1200, from bite (v).
bitmap (n.): 1973, in computer jargon, from bit (n.2) + map. Literally, a map of bits.
bitsy (adj.): 1883, from plural of bit (n.1) or a variant of bitty.
bitten: past participle of bite.
bitter (adj.): Old English biter "bitter, sharp, cutting; angry, embittered; cruel," from Proto-Germanic *bitras- (cf. Old Saxon bittar, Old Norse bitr, Dutch bitter, Old High German bittar, German bitter, Gothic baitrs "bitter"), from PIE root *bheid- "to split" (cf. Old English bitan "to bite;" see bite (v.)). Evidently the meaning drifted in prehistoric times from "biting, of pungent taste," to "acrid-tasting." Used figuratively in Old English of states of mind and words. Related: Bitterly.
bitter end (n.): In lexicons of sea language going back to 1759, the bitter end is the part of a cable which is round about the bits (two great timbers used to belay cables) when the ship is at anchor.
Bitter end of the Cable, the End which is wound about the Bitts. ["The News-Readers Pocket-Book: Or, a Military Dictionary," London, 1759]
See bit (n.1). So, when a cable is played out to the bitter end, there is no more left to play. The term began to be used c.1835 in non-nautical use and with probable influence of bitter (adj.).
bittern (n.): heron-like bird, 13c., botor, from Old French butor "bittern," perhaps from Gallo-Romance *butitaurus, from Latin butionem "bittern" + taurus "bull" (see steer (n.)); according to Pliny, so called because of its booming voice, but this seems fanciful. Modern form from 1510s.