borderline (n.) Look up borderline at Dictionary.com
1869, "strip of land along a frontier," from border (n.) + line (n.). As an adjective meaning "verging on" it is attested from 1907, originally in medical jargon.
bore (v.1) Look up bore at Dictionary.com
Old English borian "to bore through, perforate," from bor "auger," from Proto-Germanic *buron (source also of Old Norse bora, Swedish borra, Old High German boron, Middle Dutch boren, German bohren), from PIE root *bhorh- "hole."
bore (v.3) Look up bore at Dictionary.com
past tense of bear (v.).
bore (n.2) Look up bore at Dictionary.com
1778, "thing which causes ennui or annoyance by dullness;" earlier "state of boredom, fit of listless disgust" (1766); of persons who cause boredom by 1812; usually said to be a figurative extension of bore (v.1) on the notion of "move forward slowly and persistently," as a boring tool does, but OED has doubts and early evidence suggests a French connection.
Le secret d'ennuyer est celui de tout dire (The secret of being a bore is to tell everything) [Voltaire, "Sept Discours en Vers sur l'Homme," 1738]
bore (n.1) Look up bore at Dictionary.com
Old English bor "instrument for making holes by boring or turning," from the source of bore (v.1). As "hole made by boring," early 14c. Meaning "cylindrical hole through a tube, gun, etc." is from 1570s; that of "interior diameter of a tube, caliber of a gun" (whether bored or not) is from 1580s. Hence figurative slang full bore (1936) "at maximum speed," from notion of unchoked carburetor on an engine.
bore (v.2) Look up bore at Dictionary.com
"be tiresome or dull," 1768, a vogue word c. 1780-81 according to Grose (1785); see bore (n.2).
boreal (adj.) Look up boreal at Dictionary.com
"northern," late 15c., from Late Latin borealis, from Latin Boreas "north wind," from Greek Boreas, name of the god of the north wind, which is of unknown origin, perhaps related to words in Sanskrit (giri-) and Balto-Slavic (Lithuanian gire, Old Church Slavonic gora) for "mountain" (also "forest") as if "those living beyond the mountains."
borealis Look up borealis at Dictionary.com
1790, shortening of aurora borealis (q.v.).
Boreas Look up Boreas at Dictionary.com
"the north wind," late 14c., from Latin Boreas, from Greek (see boreal).
bored (adj.) Look up bored at Dictionary.com
"wearied, suffering from ennui," 1823, past participle adjective from bore (v.2).
Society is now one polished horde,
Formed of two mighty tribes, the Bores and Bored.
[Byron, "Don Juan," 1823]
Meaning "pierced, perforated, cylindrically hollow" is 1510s, from bore (v.1).
boredom (n.) Look up boredom at Dictionary.com
"state of being bored," 1852, from bore (v.1) + -dom. It also has been employed in a sense "bores as a class" (1883) and "practice of being a bore" (1864, a sense properly belonging to boreism, 1833).
borg (n.) Look up borg at Dictionary.com
fictional hostile alien hive-race in the "Star Trek" series, noted for "assimilating" defeated rivals, first introduced in "The Next Generation" TV series (debut fall 1987). Their catchphrase is "resistance is futile." According to the series creators, the name is derived from cyborg.
boring (adj.) Look up boring at Dictionary.com
1853 in reference to animals that bore, past participle adjective from bore (v.1); 1840 in the sense "wearying, annoyingly dull, causing ennui," from bore (v.2). As a verbal noun, mid-15c., "action of piercing or perforating."
Boris Look up Boris at Dictionary.com
Slavic masc. proper name, literally "fight," from Slavic root *bor- "to fight, overcome" (from PIE root *bhorh- "hole").
bork (v.) Look up bork at Dictionary.com
"to discredit a candidate for some position by savaging his or her career and beliefs," 1987, from name of U.S. jurist Robert H. Bork (1927-2012), whose Supreme Court nomination in 1987 was rejected after an intense counter-campaign.
born (adj.) Look up born at Dictionary.com
Old English boren, alternative past participle of beran (see bear (v.)). "In modern use the connexion with bear is no longer felt; the phrase to be born has become virtually an intr. verb" [OED]. Distinction between born and borne (q.v.) is 17c. From early 14c. as "possessing from birth the character or quality described" (born poet, born loser, etc.). From 1710 as "innate, inherited;" colloquial expression in (one's) born days "in (one's) lifetime" is by 1742.
born-again (adj.) Look up born-again at Dictionary.com
of Protestant Christians, "regenerated in spirit and character by a 'new birth' in Christ," by 1920, based on John iii.3. Used in figurative (non-religious) sense by 1977.
borne Look up borne at Dictionary.com
"carried, sustained, endured," past tense and participle of bear (v.) in all senses not related to birth. See born.
Borneo Look up Borneo at Dictionary.com
large island in Indonesia, from Portuguese alteration of Brunei, which is today the name of a sultanate on the island. This is Hindi and probably ultimately from Sanskrit bhumi "land, region." Related: Bornean.
Bornholm Look up Bornholm at Dictionary.com
island in the southern Baltic, from Old Danish Burgundarholm, from Burgundar "the Burgundians" (see Burgundy) + holm "island" (see holm). The Burgundians migrated from there to France 5c.
boron (n.) Look up boron at Dictionary.com
non-metallic chemical element, 1812, from borax + ending abstracted unetymologically from carbon (its properties somewhat resemble those of carbon). Originally called boracium by Humphrey Davy because it was drawn from boracic acid. Related: Boric.
borough (n.) Look up borough at Dictionary.com
Old English burg, burh "a dwelling or dwellings within a fortified enclosure," from Proto-Germanic *burgs "hill fort, fortress" (source also of Old Frisian burg "castle," Old Norse borg "wall, castle," Old High German burg, buruc "fortified place, citadel," German Burg "castle," Gothic baurgs "city"), from PIE root *bhergh- (2) "high," with derivatives referring to hills, hill forts, and fortified elevations.

In German and Old Norse, chiefly as "fortress, castle;" in Gothic, "town, civic community." Meaning shifted in Old English from "fortress," to "fortified town," then simply "town" (16c., especially one possessing municipal organization or sending representatives to Parliament). In some U.S. states (originally Pennsylvania, 1718) often an incorporated town; in Alaska, however, it is the equivalent of a county. As one of the five divisions of New York City, 1897; as a London administrative district, 1899.

The Scottish form is burgh. The Old English dative singular byrig survives in many place names as -bury.
borrow (v.) Look up borrow at Dictionary.com
Old English borgian "to lend, be surety for," from Proto-Germanic *borg "pledge" (source also of Old English borg "pledge, security, bail, debt," Old Norse borga "to become bail for, guarantee," Middle Dutch borghen "to protect, guarantee," Old High German boragen "to beware of," German borgen "to borrow; to lend"), from PIE root *bhergh- (1) "to hide, protect."

Sense shifted in Old English to the modern one, "take or obtain (something) on pledge to return it or security given," apparently on the notion of collateral deposited as security for something borrowed. Figurative use from early 13c.; borrowed time is from 1898. As an operation in subtraction, 1590s. Related: Borrowed; borrowing.
borscht (n.) Look up borscht at Dictionary.com
"Russian soup made with beets and cabbage," 1884, from Russian borshch "cow parsnip," which was an original recipe ingredient. Borscht belt "region of predominantly Jewish resorts in and around the Catskill Mountains of New York" (also known as the Yiddish Alps) is by 1938.
bort (n.) Look up bort at Dictionary.com
"waste diamonds, small chips from diamond-cutting," 1620s, of unknown origin, perhaps related to Old French bort "bastard."
Borussia Look up Borussia at Dictionary.com
alternative form of Prussia (q.v.).
borzoi (n.) Look up borzoi at Dictionary.com
Russian wolfhound, 1887, from Russian borzoy, literally "swift, quick" (compare Czech brzy, Serbo-Croatian brzo "quickly," Lithuanian bruzdeti "to hurry").
bose (n.) Look up bose at Dictionary.com
"to seek for hollows underground by ramming the ground and observing the vibrations," 1929, ultimately from Scottish word boss "hollow, empty" (1510s), earlier a noun meaning "small cask, wine flask" (late 14c.).
bosh (n.) Look up bosh at Dictionary.com
"empty talk, nonsense," 1850, from Turkish, literally "empty." Introduced in "Ayesha," popular 1834 romance novel by J.J. Morier (1780-1849).
Bosnia Look up Bosnia at Dictionary.com
named for the River Bosna, which is perhaps from an Indo-European root *bhog- "current." As a name or adjective for someone there, Bosnian (1788) is older in English than Bosniac (1836, from Russian Bosnyak).
bosom (n.) Look up bosom at Dictionary.com
Old English bosm "breast; womb; surface; ship's hold," from West Germanic *bosm- (source also of Old Frisian bosm, Old Saxon bosom, Middle Dutch boesem, Dutch boezem, Old High German buosam, German Busen "bosom, breast"), perhaps from PIE root *bhou- "to grow, swell," or *bhaghus "arm" (in which case the primary notion would be "enclosure formed by the breast and the arms").

Bosoms in the narrowed or euphemistic meaning "a woman's breasts" is from 1959; bosomy "big-breasted" is from 1928. Bosom-friend is attested 1580s; bosom buddy from 1920s. Abraham's bosom "the abode of the blessed" is from Luke xvi.19-31.
boson (n.) Look up boson at Dictionary.com
class of subatomic particles which obeys Bose-Einstein statistics, named for Indian physicist Satyendra Nath Bose (1894-1974) + subatomic particle suffix -on.
Bosphorus Look up Bosphorus at Dictionary.com
a Latin error for bosporus, from Greek bosporos, a name applied to several channels or straits between seas, literally "ox's ford," from bous "ox" (from PIE root *gwou- "ox, bull, cow") + poros "passage, ford" (see pore (n.)). Applied especially to that between the Sea of Marmora and the Black Sea (the Thracian Bosphorus).
boss (n.2) Look up boss at Dictionary.com
"protuberance, button," c. 1300, from Old French boce "a hump, swelling, tumor" (12c., Modern French bosse), from either Frankish *botija or Vulgar Latin *bottia, both of uncertain origin.
boss (n.1) Look up boss at Dictionary.com
"overseer, one who employs or oversees workers," 1640s, American English, from Dutch baas "a master," Middle Dutch baes, of obscure origin. If original sense was "uncle," perhaps it is related to Old High German basa "aunt," but some sources discount this theory.

The Dutch form baas is attested in English from 1620s as the standard title of a Dutch ship's captain. The word's popularity in U.S. may reflect egalitarian avoidance of master (n.) as well as the need to distinguish slave from free labor. The slang adjective meaning "excellent" is recorded in 1880s, revived, apparently independently, in teen and jazz slang in 1950s.
boss (v.2) Look up boss at Dictionary.com
c. 1400, "to swell out; to beat or press into a raised ornament," from boss (n.2). From 1620s as "to furnish with bosses." Related: Bossed; bossing.
boss (v.1) Look up boss at Dictionary.com
"be master or manager of, to order and direct as a boss," 1856, from boss (n.1). Related: Bossed; bossing.
bossa nova (n.) Look up bossa nova at Dictionary.com
Brazilian style of music, 1962, from Portuguese, literally "new tendency."
bossy (adj.) Look up bossy at Dictionary.com
1540s, "swelling, projecting and rounded, decorated with bosses" from boss (n.2). Meaning "domineering, fond of ordering people about" is recorded 1882, from boss (n.1) + -y (2). As a common cow name (by 1844) it represents Latin bos "cow" (from PIE root *gwou- "ox, bull, cow"). Related: Bossily; bossiness.
Boston Look up Boston at Dictionary.com
U.S. city, 1630, named for town in Lincolnshire, a region from which many settlers came to New England. The name is said to be literally "Botolph's Stone," probably from the name of some Anglo-Saxon landowner (Old English Botwulf). Boston Massacre was March 5, 1770; three civilians killed, two mortally wounded. The Boston Tea Party (1824) took place on Dec. 16, 1773 (see tea party). Related: Bostonian.
bosun (n.) Look up bosun at Dictionary.com
a mid-19c. respelling to reflect the modern pronunciation of boatswain.
bot (n.) Look up bot at Dictionary.com
in internet sense, c. 2000, short for robot. Its modern use has curious affinities with earlier uses, such as "parasitical worm or maggot" (1520s), of unknown origin; and Australian-New Zealand slang "worthless, troublesome person" (World War I-era). The method of minting new slang by clipping the heads off words does not seem to be old or widespread in English. Examples (za from pizza, zels from pretzels, rents from parents) are American English student or teen slang and seem to date back no further than late 1960s. Also compare borg, droid.
botanic (adj.) Look up botanic at Dictionary.com
"pertaining to the science or study of plants," 1650s, from French botanique (17c.) or directly from Medieval Latin botanicus, from Greek botanikos "of herbs," from botane "a plant, grass, pasture, fodder." The Greek words seems to have more to do with pasturage than plants; compare related botamia "pastures, meadows," boter "herdsman," boton "grazing beast."
botanical (adj.) Look up botanical at Dictionary.com
"concerned with the study or cultivation of plants," 1650s, from botanic + -al. Related: Botanically.
botanist (n.) Look up botanist at Dictionary.com
"one who studies botany," 1680s; see botany + -ist.
botany (n.) Look up botany at Dictionary.com
"the science of plants," 1690s, from botanic. The -y is from astronomy, etc. Botany Bay in Australia so called by Capt. Cook on account of the great variety of plants found there; later it was a convict settlement.
botch (v.) Look up botch at Dictionary.com
late 14c., bocchen "to repair," later, "repair clumsily, to spoil by unskillful work" (1520s); of unknown origin. Middle English Dictionary says probably the same as bocchen "to swell up or fester; to bulge or project" (though this is only from early 15c. and OED denies a connection) which is from Old North French boche, Old French boce, a common Romanic word of uncertain origin. Related: Botched; botching.

As a noun, "a bungled or ill-finished part," from c. 1600, perhaps from the verb, but compare Middle English bocche "a boil, a pathological swelling, a tumor" (late 14c.), used especially of glandular swellings from the plague, also figuratively "a corrupt person; a rotten condition" (late 14c.), "a hump on a cripple" (early 14c.), which probably is from Old North French boche, Old French boce, a common Romanic word of uncertain origin.
both (adj., pron.) Look up both at Dictionary.com
"the two, the one and the other," there are several theories, all similar, and deriving the word from the tendency to say "both the." One is that it is Old English begen (masc.) "both" (from Proto-Germanic *ba, from PIE *bho "both") + extended base. Another traces it to the Proto-Germanic formula represented in Old English by ba þa "both these," from ba (feminine nominative and accusative of begen) + þa, nominative and accusative plural of se "that." A third traces it to Old Norse baðir "both," from *bai thaiz "both the," from Proto-Germanic *thaiz, third person plural pronoun. Compare similar formation in Old Frisian bethe, Dutch beide, Old High German beide, German beide, Gothic bajoþs.
bother (v.) Look up bother at Dictionary.com
1718, also bauther, bather, bodder, "to bewilder, confuse;" 1745 as "give trouble to," probably from Anglo-Irish pother, because its earliest use was by Irish writers (Sheridan, Swift, Sterne). Perhaps from Irish bodhairim "I deafen." Related: Bothered; bothering. As a noun from 1803.
botheration (n.) Look up botheration at Dictionary.com
"annoyance, petty vexation," 1797, noun of action from bother (v.).