Online Etymology Dictionary

broody (adj.): 1510s, "apt to breed," from brood (v.) + -y (2). Figuratively, of persons, from 1851. Also, in modern use, sometimes "full of maternal yearning." Related: Broodily; broodiness.
brook (n.): "small stream," Old English broc "flowing stream, torrest," of obscure origin, probably from Proto-Germanic *broka- which yielded words in German (Bruch) and Dutch (broek) that have a sense of "marsh." In Sussex and Kent, it means "water-meadow," and in plural, "low, marshy ground."
brook (v.): "to endure," Old English brucan "use, enjoy, possess; eat; cohabit with," from Proto-Germanic *bruk- "to make use of, enjoy" (source also of Old Saxon brukan, Old Frisian bruka, Old High German bruhhan, German brauchen "to use," Gothic brukjan), from PIE root *bhrug- "to make use of, have enjoyment of" (source also of Latin fructus). Sense of "use" applied to food led to "be able to digest," and by 16c. to "tolerate."
Brooke: fem. proper name, rare in U.S. before 1965, popular 1980s, 1990s.
Brooklyn: New York City borough, named for village founded there 1646 and named for Dutch township of Breukelen near Utrecht; from Old High German bruoh "moor, marshland;" spelling of U.S. place name influenced by brook (n.), which probably is distantly related.
broom (n.): Old English brom "broom, brushwood," the common flowering shrub whose twigs were tied together to make a tool for sweeping, from Proto-Germanic *bræmaz "thorny bush" (source also of Dutch braam, German Brombeere "blackberry"), from PIE root *bh(e)rem- "to project, a point."

Traditionally, both the flowers and sweeping with broom twigs were considered unlucky in May (Suffolk, Sussex, Wiltshire, etc.). The witch's flying broomstick originally was one among many such objects (pitchfork, trough, bowl), but the broomstick became fixed as the popular tool of supernatural flight via engravings from a famous Lancashire witch trial of 1612.
brose (n.): 1650s, Scottish, earlier browes, from Old French broez, nominative of broet (13c.) "stew, soup made from meat broth," diminutive of breu, from Medieval Latin brodium, from Old High German brod "broth" (see broth).
broth (n.): Old English broþ, from Proto-Germanic *bruthan (source also of Old High German *brod), from verb root *bhreue- "to heat, boil, bubble; liquid in which something has been boiled" (source also of Old English breowan "to brew;" see brew (v.)). Picked up from Germanic by the Romanic and Celtic languages.

The Irishism broth of a boy, which is in Byron, was "thought to originate from the Irish Broth, passion -- Brotha passionate, spirited ..." [Farmer], and if so is not immediately related.
brothel (n.): "bawdy house," 1590s, shortened from brothel-house, from brothel "prostitute" (late 15c.), earlier "vile, worthless person" of either sex (14c.), from Old English broðen past participle of breoðan "deteriorate, go to ruin," from Proto-Germanic *breuthan "to be broken up," related to *breutan "to break" (see brittle). In 16c. brothel-house was confused with unrelated bordel (see bordello) and the word shifted meaning from a person to a place.
brother (n.): Old English broþor, from Proto-Germanic *brothar (source also of Old Norse broðir, Danish broder, Old Frisian brother, Dutch broeder, German Bruder, Gothic bróþar), from PIE root *bhrater (source also of Sanskrit bhrátár-, Old Persian brata, Greek phratér, Latin frater, Old Irish brathir, Welsh brawd, Lithuanian broterelis, Old Prussian brati, Old Church Slavonic bratru, Czech bratr "brother").

A highly stable word across the Indo-European languages. In the few cases where other words provide the sense, it is where the cognate of brother had been applied widely to "member of a fraternity," or where there was need to distinguish "son of the same mother" and "son of the same father." E.g. Greek adelphos, probably originally an adjective with frater and meaning, specifically, "brother of the womb" or "brother by blood;" and Spanish hermano "brother," from Latin germanus "full brother." As a familiar term of address from one man to another, it is attested from 1912 in U.S. slang; the specific use among blacks is recorded from 1973.
Brother Jonathan (n.): sobriquet for "United States," 1816, often connected with Jonathan Trumbull (1740-1809) of Connecticut, called Brother Jonathan by George Washington, who often sought his advice, somehow in reference to 2 Sam i:26.
brother-in-law (n.): c. 1300; also brother in law; see brother. In Arabic, Urdu, Swahili, etc., brother-in-law, when addressed to a male who is not a brother-in-law, is an extreme insult, with implications of "I slept with your sister."
brotherhood (n.): equivalent of Old English broþerrede "fellowship, brotherhood," with ending as in kindred; in early Middle English the word was brotherhede with ending as in maidenhead. The modern word, with -hood, is from 15c. Originally "relationship of a brother," also "friendly companionship." Concrete sense of "an association, a fraternity" is from mid-14c. in the Middle English word (later also "labor union," 1880s). Old English also had broðorscipe "brothership," broðorsibb "kinship of brothers."
Oh, the Protestants hate the Catholics,
And the Catholics hate the Protestants,
And the Hindus hate the Muslims,
And everybody hates the Jews.

[Tom Lehrer, "National Brotherhood Week" lyrics, 1965]
brotherliness (n.): Old English broðorlichnes; see brotherly + -ness.
brotherly (adj.): Old English broðorlic; see brother + -ly (1).
brougham (n.): 1851, one-horse closed carriage with two or four wheels, for two or four persons, from first Lord Brougham (1778-1868). The family name is from a place in Westmoreland.
brought: past tense and past participle of bring (v.). For explanation of the form development, see thought.
brouhaha (n.): 1890, from French brouhaha (1550s), said by Gamillscheg to have been, in medieval theater, "the cry of the devil disguised as clergy." Perhaps from Hebrew barukh habba' "blessed be the one who comes," used on public occasions (as in Psalm 118).
brow (n.): early 14c., browes, brues "brow, forehead, eyebrow," earlier brouwes (c. 1300), bruwen (c. 1200), from Old English bru, probably originally "eyebrow," but extended to "eyelash," then "eyelid" by association of the hair of the eyebrow with the hair of the eyelid, the eyebrows then becoming Old English oferbrua "overbrows" (early Middle English uvere breyhes or briges aboue þe eiges).

The general word for "eyebrow" in Middle English was brew, breowen (c. 1200), from Old English bræw (West Saxon), *brew (Anglian), from Proto-Germanic *bræwi- "blinker, twinkler" (source also of Old Frisian bre, Old Saxon brawa, Middle Dutch brauwe "eyelid," Old High German brawa"eyebrow," Old Norse bra "eyebrow," Gothic brahw "twinkle, blink," in phrase in brahwa augins "in the twinkling of an eye").

Old English bru is from Proto-Germanic *brus- "eyebrow" (source also of Old Norse brun), from PIE *bhru- "eyebrow" (source also of Sanskrit bhrus "eyebrow," Greek ophrys, Old Church Slavonic bruvi, Lithuanian bruvis "brow," Old Irish bru "edge"). The -n- in the Old Norse (brun) and German (braune) forms of the word are from a genitive plural inflection.

Words for "eyelid," "eyelash," and "eyebrow" changed about maddeningly in Old and Middle English (and in all the West Germanic languages). By 1530s, brow had been given an extended sense of "forehead," especially with reference to movements and expressions that showed emotion or attitude.
browbeat (v.): "to bully," originally "to bear down with stern or arrogant looks," 1580s, from brow + beat (v.).
[I]t appears from the earliest quotations ... that the brow in question was that of the beater, not of the beaten party; but it is not evident whether the meaning was 'to beat with one's (frowning) brows,' or 'to beat (?lower) one's brows at.' [OED]
Related: Browbeaten; browbeating.
brown (adj.): Old English brun "dark, dusky," developing a definite color sense only 13c., from Proto-Germanic *brunaz (source also of Old Norse brunn, Danish brun, Old Frisian and Old High German brun, Dutch bruin, German braun), from PIE *bher- (3) "shining, brown" (source also of Lithuanian beras "brown"), related to *bheros "dark animal" (compare beaver, bear (n.), and Greek phrynos "toad," literally "the brown animal").

The Old English word also had a sense of "brightness, shining," preserved only in burnish. The Germanic word was adopted into Romanic (Middle Latin brunus, Italian and Spanish bruno, French brun). Brown Bess, slang name for old British Army flintlock musket, first recorded 1785.
brown (v.): c. 1300, "to become brown," from brown (adj.). From 1560s as "to make brown." Related: Browned; browning.
brown (n.): "brown color," c. 1600, from brown (adj.).
Brown Shirt (n.): generic term for "Nazi, fascist," especially of the thuggish sort, 1934, originally (1922) in reference to the German Sturmabteilung, Nazi militia founded 1921; they were called Brown Shirts in English because of their uniforms.
brown-bag (v.): "to bring lunch or liquor in a brown paper bag," 1970, from brown (adj.) + bag (n.). Related: Brown-bagging.
brown-nose (v.): also brownnose, 1939, American English colloquial, said to be military slang originally, from brown (adj.) + nose (n.), "from the implication that servility is tantamount to having one's nose in the anus of the person from whom advancement is sought" [Webster, 1961]. Related: Brown-noser, brown-nosing (both 1950).
brownfield (n.): abandoned or disused industrial land, often contaminated to some degree, 1992, American English, from brown (adj.) + field (n.).
Brownian movement (n.): 1871, for Scottish scientist Dr. Robert Brown (1773-1858), who first described it.
brownie (n.): "benevolent goblin supposed to haunt old farmhouses in Scotland," 1510s, diminutive of brown "a wee brown man" (see brown (adj.)). The name for the junior branch of the Girl Guides or Girl Scouts is 1916, in reference to uniform color. Brownie point (1963) is sometimes associated with Brownie in the Scouting sense but is perhaps rather from brown-nose.
Browning: one of a range of U.S.-made weapons, 1905, named for inventor, John M. Browning (1855-1926) of Utah.
brownstone (n.): "dark sandstone," 1858, from brown (adj.) + stone (n.). As "house or building fronted with brownstone" from 1948.
browse (v.): mid-15c., "feed on buds," from Middle French brouster, from Old French broster "to sprout, bud," from brost "young shoot, twig," probably from Proto-Germanic *brust- "bud, shoot," from PIE *bhreus- "to swell, sprout" (see breast (n.)). Lost its final -t in English on the mistaken notion that the letter was a past participle inflection. Figurative extension to "peruse" (books) is 1870s, American English. Related: Browsed; browsing.
browser (n.): 1845, "animal which browses," agent noun from browse (v.). In the computer sense by 1982.
The first browser was invented at PARC by Larry Tesler, now a designer at Apple Computer. Tesler's first Smalltalk browser was a tree-structured device. It enabled programmers to hunt quickly for items in a Smalltalk dictionary. ["InfoWorld" magazine, vol. v., no. 4, Jan. 24, 1983]
Bruce: a Norman surname, but etymology from Brix (place in La Manche, Normandy) is now considered doubtful ["Dictionary of English Surnames"]. Originated in Britain with Robert de Bruis, a baron listed in the Domesday Book. His son, a friend of David I, king of Scotland, was granted by him in 1124 the lordship of Annandale, and David's son, Robert, founded the Scottish House of Bruce. As a given name for U.S. males, most popular for boys born c. 1946-1954.
brucellosis (n.): 1930, Modern Latin, named for Scottish physician Sir David Bruce (1855-1931), who discovered the bacteria that caused it (1887).
bruin (n.): "bear," late 15c., from Middle Dutch Bruin, name of the bear in "Reynard the Fox" fables; literally "brown;" cognate with Old English brun (see brown (adj.)).
bruise (v.): Old English brysan "to crush, bruise, pound," from Proto-Germanic *brusjan, from PIE root *bhreu- "to smash, cut, break up" (source also of Old Irish bronnaim "I wrong, I hurt;" Breton brezel "war," Vulgar Latin brisare "to break"). Merged by 17c. with Anglo-French bruiser "to break, smash," from Old French bruisier "to break, shatter," perhaps from Gaulish *brus-, from the same PIE root. Related: Bruised; bruising.
bruise (n.): 1540s, from bruise (v.).
bruiser (n.): "a pugilist," 1744, agent noun from bruise (v.).
bruit (v.): "to report," 1520s, from bruit (n.) "rumor, tiding, fame, renown" (mid-15c.), from French bruit (n.), from bruire "to make noise, roar," which is of uncertain origin. Related: Bruited; bruiting.
brulee (adj.): from French brûlée "burned," from brûler, from Old French brusler (11c.); see broil (v.1). Crème brûlée was known in English by various names from early 18c., including a translated burnt cream.
brumal (adj.): "belonging to winter," 1510s, from Latin brumalis, from bruma "winter" (see brume). The Latin word also is the ultimate source of Brumaire, second month (Oct. 22-Nov. 20) in calendar of the French Republic, literally "the foggy month," coined 1793 by Fabre d'Eglantine from French brume "fog" (see brume).
brume (n.): "fog, mist," 1808, from French brume "fog" (14c.), in Old French, "wintertime," from Latin bruma "winter," perhaps with an original sense "season of the shortest day," from *brevima, contracted from brevissima, superlative of brevis "short" (see brief (adj.)).
brummagem (adj.): "cheap and showy," 19c., from a noun, from the vulgar pronunciation of Birmingham, England, in reference to articles mass-manufactured there. The word also recalls Birmingham's old reputation for counterfeiting.
brunch: 1896, British student slang merger of breakfast and lunch.
To be fashionable nowadays we must 'brunch'. Truly an excellent portmanteau word, introduced, by the way, last year, by Mr. Guy Beringer, in the now defunct Hunter's Weekly, and indicating a combined breakfast and lunch. ["Punch," Aug. 1, 1896]
brunet (n.): "dark-complexioned person," 1887, from French brunet, diminutive of brun "brown," which is from a Germanic source (see brown (adj.)).
brunette (adj.): 1660s, from French brunette (masc. brunet), from Old French brunet "brownish, brown-haired, dark-complexioned," fem. diminutive of brun "brown" (12c.), of West Germanic origin (see brown (adj.)). As a noun, "woman of a dark complexion," from 1710. The metathesized form, Old French burnete, is the source of the surname Burnett. Burnete also was used of a wool-dyed cloth of superior quality, originally dark brown.
brung: dialectal past tense and past participle of bring (v.).
Bruno: masc. proper name, from Old High German Bruno, literally "brown" (see brown (adj.)).
brunt (n.): early 14c., "a sharp blow," of uncertain origin, perhaps from Old Norse brundr "sexual heat," or bruna "to advance like wildfire." Meaning "chief force" is first attested 1570s.