birthday (n.) Look up birthday at Dictionary.com
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.) Look up birthday suit at Dictionary.com
first attested 1730s, but probably much older. The notion is the suit of clothes one was born in, i.e., no clothes at all. Compare Middle English mother naked "naked as the day one was born;" Middle Dutch moeder naect, German mutternackt.
birthmark (n.) Look up birthmark at Dictionary.com
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.) Look up birthplace at Dictionary.com
also birth-place, c. 1600, from birth (n.) + place (n.).
birthright (n.) Look up birthright at Dictionary.com
also birth-right, 1530s, from birth (n.) + right (n.). Used as an adjective from 1650s, especially by Quakers.
birthstone (n.) Look up birthstone at Dictionary.com
1874, from birth (n.) + stone (n.).
bis- Look up bis- at Dictionary.com
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.) Look up biscotti at Dictionary.com
1990s, from Italian biscotti, plural of biscotto, from Old Italian biscotto, from Medieval Latin biscoctum (see biscuit).
biscuit (n.) Look up biscuit at Dictionary.com
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.) Look up bisect at Dictionary.com
"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.) Look up bisection at Dictionary.com
"division in two," 1650s, noun of state from bisect. Related: Bisectional.
bisector (n.) Look up bisector at Dictionary.com
1821; agent noun from bisect.
bisexual (adj.) Look up bisexual at Dictionary.com
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, and compare bisexuality. Not in general use until 1950s. Ambisexual was proposed in this sense early 20c.
I suggest that the term ambisexuality be used in psychology instead of the expression "bisexual predisposition." This would connote that we understand by this predisposition, not the presence of male and female material in the organism (Fliess), nor of male and female sex hunger in the mind, but the child's psychical capacity for bestowing his erotism, originally objectless, on either the male or the female sex, or on both. [S. Ferenczi, "Sex in Psycho-Analysis," transl. Ernest Jones, Boston, 1916]
bisexuality (n.) Look up bisexuality at Dictionary.com
"attraction to both sexes" 1892, in translation of Krafft-Ebing; see bisexual + -ity.
bishop (n.) Look up bishop at Dictionary.com
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 "one that watches, one that looks after; a guardian, protector" (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.) Look up bishopric at Dictionary.com
Old English bisceoprice "diocese, province of a bishop," from bishop + rice "realm, dominion, province," from Proto-Germanic *rikja "rule," from PIE root *reg- "move in a straight line," with derivatives meaning "to direct in a straight line," thus "to lead, rule."
Bismarck Look up Bismarck at Dictionary.com
"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 Look up bismillah at Dictionary.com
first attested in English in Byron, from Arabic bi'smillah(i) "in the name of God" (Allah).
bismuth (n.) Look up bismuth at Dictionary.com
1660s, from obsolete German Bismuth, also Wismut, Wissmuth (early 17c.), which is 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.) Look up bison at Dictionary.com
c. 1600, from French bison (15c.), from Latin bison "wild ox," borrowed from Proto-Germanic *wisand- "aurochs" (source also of 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) Look up bisque at Dictionary.com
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) Look up bisque at Dictionary.com
"unglazed porcelain," 1660s, alteration of biscuit.
bissextile Look up bissextile at Dictionary.com
1580s (n.); 1590s (adj.), in reference to Roman leap year, from Late Latin (annus) bisextilis "leap year," literally "the twice sixth-day, a year containing a second sixth day," because the sixth day before the Calends of March was doubled.
bistro (n.) Look up bistro at Dictionary.com
1906, from French bistro (1884), originally Parisian slang for "little wineshop or restaurant," which is 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.2) Look up bit at Dictionary.com
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.) Look up bit at Dictionary.com
past tense of bite.
bit (n.1) Look up bit at Dictionary.com
"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 (source also of 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- from PIE root *bheid- "to split."

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."
bitch (n.) Look up bitch at Dictionary.com
Old English bicce "female dog," probably from Old Norse bikkjuna "female of the dog" (also fox, wolf, and occasionally other beasts), which is 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 African-American vernacular) 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.) Look up bitch at Dictionary.com
"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 (as in Chaucer's bicched bones "unlucky dice"), which despite the hesitation of OED, seems to be a derivative of bitch (n.).
bitching (adj.) Look up bitching at Dictionary.com
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.) Look up bitchy at Dictionary.com
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 (n.) Look up bite at Dictionary.com
c. 1200, from bite (v.).
bite (v.) Look up bite at Dictionary.com
Old English bitan (class I strong verb; past tense bat, past participle biten), from Proto-Germanic *bitan (source also of 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," with derivatives in Germanic referring to biting.

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 off more than one can chew (c. 1880) is U.S. slang, from plug tobacco.
bitmap (n.) Look up bitmap at Dictionary.com
1973, in computer jargon, from bit (n.2) + map. Literally, a map of bits.
bitsy (adj.) Look up bitsy at Dictionary.com
1883, from plural of bit (n.1) or a variant of bitty.
bitten Look up bitten at Dictionary.com
past participle of bite.
bitter (adj.) Look up bitter at Dictionary.com
Old English biter "bitter, sharp, cutting; angry, embittered; cruel," from Proto-Germanic *bitras- (source also of Old Saxon bittar, Old Norse bitr, Dutch bitter, Old High German bittar, German bitter, Gothic baitrs "bitter"), from suffixed form of PIE root *bheid- "to split" (source also of 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.) Look up bitter end at Dictionary.com
In lexicons of sea language going back to 1759, the bitter end is the part of a cable which is round about the bitts (the 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]
Bitts is from a Germanic word (compare Old Norse biti "crossbeam") related to 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.) Look up bittern at Dictionary.com
heron-like bird, 13c., botor, from Old French butor "bittern," perhaps from Gallo-Roman *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.
bitterness (n.) Look up bitterness at Dictionary.com
Old English biternys "bitterness, grief;" see bitter + -ness. Figurative sense (of feelings, etc.) is attested earlier than literal sense (of taste), which will surprise no one who reads any amount of Anglo-Saxon literature.
bitters (n.) Look up bitters at Dictionary.com
1713, from bitter. So called for its taste.
bittersweet (n.) Look up bittersweet at Dictionary.com
also bitter-sweet, late 14c., used especially in Middle English in reference to a type of apple, from bitter (adj.) + sweet (adj.). As an adjective, attested from 1610s. Greek had a similarly formed compound, glykypikros, literally "sweet-bitter."
BitTorrent Look up BitTorrent at Dictionary.com
peer-to-peer file sharing protocol, implemented in 2001, from bit (n.2) in the computing sense + torrent.
bitty (adj.) Look up bitty at Dictionary.com
"small," 1873, baby-talk, from bit (n.1) + -y (2).
bitumen (n.) Look up bitumen at Dictionary.com
mid-15c., from Latin bitumen "asphalt," probably, via Oscan or Umbrian, from Celtic *betu- "birch, birch resin" (compare Gaulish betulla "birch," used by Pliny for the tree supposedly the source of bitumen).
bituminous (adj.) Look up bituminous at Dictionary.com
1610s, from French bitumineux, from Latin bituminosus, from bitumen (see bitumen).
The Plain, wherein a black bituminous gurge Boiles out from under ground, the mouth of Hell. ["Paradise Lost," XII.41]
bivalence (n.) Look up bivalence at Dictionary.com
1868; see bivalent + -ence.
bivalency (n.) Look up bivalency at Dictionary.com
1872; see bivalent + -ency.
bivalent (adj.) Look up bivalent at Dictionary.com
1864, of chemicals, 1899, of chromosomes, from bi- + -valent, from Latin valentem, present participle of valere "be worth" (see valiant).
bivalve (adj.) Look up bivalve at Dictionary.com
1660s in reference to mollusks with double shells; 1670s in reference to shutters or doors; from bi- + valve. The noun is 1680s in the mollusk sense.