Online Etymology Dictionary

beeline (n.): also bee-line, 1838, American English, from bee + line (n.), in reference to the homing of bees in the field.
TO LINE BEES is to track wild bees to their homes in the woods. One who follows this occupation is called a bee hunter. [Bartlett, 1859]
The expression is attested from 1827.
Beelzebub: Old English Belzebub, Philistine god worshipped at Ekron (2 Kings i:2), from Latin, used in Vulgate for New Testament Greek beelzeboub, from Hebrew ba'al-z'bub "lord of the flies," from ba'al "lord" (see Baal) + z'bhubh "fly." By later Christian writers often taken as another name for "Satan," though Milton made him one of the fallen angels. Baal being originally a title, it was applied by the Hebrews to neighboring divinities based on their attributes; other examples include Baal-berith "the covenant lord," god of the Shechemites; Baal-peor "lord of the opening," a god of Moab and Midian.
been (v.): past participle of be. Dismissive slang phrase been there, done that attested from 1994 (been there "had the experience," usually of something disreputable, is from 1880s).
beep (interj.): 1927, imitative of automobile horns (originally of the sound of a certain type of automobile horn among several types in use in the years after the klaxon horn was brought into use c. 1910). Used as a noun and verb by 1929. Related: Beeped; beeping.
beeper (n.): "device that emits beeps," 1946, agent noun from beep (v.).
beer (n.): Old English beor "strong drink, beer, mead," a word of much-disputed and ambiguous origin, cognate with Old Frisian biar, Middle Dutch and Dutch bier, Old High German bior, German Bier.

Probably a 6c. West Germanic monastic borrowing of Vulgar Latin biber "a drink, beverage" (from Latin infinitive bibere "to drink;" see imbibe). Another suggestion is that it comes from Proto-Germanic *beuwoz-, from *beuwo- "barley." The native Germanic word for the beverage was the one that yielded ale (q.v.).
Beer was a common drink among most of the European peoples, as well as in Egypt and Mesopotamia, but was known to the Greeks and Romans only as an exotic product. [Buck]
They did have words for it, however. Greek brytos, used in reference to Thracian or Phrygian brews, was related to Old English breowan "brew;" Latin zythum is from Greek zythos, first used of Egyptian beer and treated as an Egyptian word but perhaps truly Greek and related to zyme "leaven." French bière is from Germanic. Spanish cerveza is from Latin cervesia "beer," perhaps related to Latin cremor "thick broth."

Old Church Slavonic pivo, source of the general Slavic word for "beer," is originally "a drink" (compare Old Church Slavonic piti "drink"). French bière is a 16c. borrowing from German. U.S. slang beer goggles, through which every potential romantic partner looks desirable, is from 1986.
beery (adj.): 1848, from beer (n.) + -y (2). Related: Beerily; beeriness.
beestings (n.): "colostrum," Old English bysting, from beost, a general West Germanic word (cognates: Old High German biost, German Biest, Middle Dutch and Dutch biest) of unknown origin.
beeswax (n.): 1670s, from genitive of bee + wax. As a jocular alteration of business (usually in an injunction to someone to mind his own) attested from 1934 in Lower East Side slang as reproduced in Henry Roth's "Call It Sleep."
beet (n.): Old English bete "beet, beetroot," from Latin beta, said to be of Celtic origin. Common in Old English, then lost till c. 1400. Still usually spoken of in plural in U.S. A general West Germanic borrowing, cognates: Old Frisian bete, Middle Dutch bete, Old High German bieza, German Beete.
beetle (n.1): type of insect, Old English bitela "beetle," literally "little biter," from bitel "biting," related to bitan "to bite" (see bite). As a nickname for the original Volkswagen car, 1946, translating German Käfer.
beetle (v.): "project, overhang," c. 1600, back-formation from bitelbrouwed "grim-browed, sullen" (mid-14c.), from bitel "sharp-edged, sharp" (c. 1200), probably a compound from Old English *bitol "biting, sharp," related to bite, + brow, which in Middle English meant "eyebrow," not "forehead." Meaning "to overhang dangerously" (of cliffs, etc.) is from c. 1600. Related: Beetled; beetling.
beetle (n.2): beating tool, Old English bietel, from Proto-Germanic *bautilo-z, from *bautan "to beat" (see beat (v.)).
beeves (n.): original plural of beef (compare boevz, plural of Old French buef), now only in restricted use.
befall (v.): Old English befeallan "to deprive of; fall to, be assigned to; befall," from be- "by, about" + feallan (see fall). Compare Old Frisian bifalla, Old Saxon, Old High German bifallan, German befallen. Related: Befell; befalling.
befit (v.): mid-15c., from be- + fit (v.). Related: Befitted; befitting.
befitting (adj.): 1560s, present participle adjective from befit (q.v.). Related: Befittingly.
befool (v.): late 14c., from be- + fool (n.). Related: Befooled; befooling.
before (adv., prep.): Old English beforan "before, in front of, in the presence of, in former times," from Proto-Germanic *bi- "by" + *forana "from the front," adverbial derivative of *fora (see fore (adv.)). Compare Old Frisian bifara, Old Saxon biforan, Old High German bifora, German bevor. Contrasting before and after in illustrations is from Hogarth (1768). Before the mast in old sailing ships denoting "common sailor," is from the place of their berths, in front of the fore-mast.
beforehand (adv., adj.): also before-hand, early 13c., from before + hand, which here is of uncertain signification, unless the original notion is payment in advance or something done before another's hand does it. Hyphenated from 18c., one word from 19c.
befoul (v.): early 14c., from be- + foul (v.). Related: Befouled; befouling.
befriend (v.): 1550s, from be- + friend (n.). Related: Befriended; befriending.
befuddle (v.): "confuse," 1873, from be- + fuddle; originally "to confuse with strong drink or opium" (by 1832). An earlier word in the same sense was begunk (1725). Related: Befuddled; befuddling.
beg (v.): c. 1200, perhaps from Old English bedecian "to beg," from Proto-Germanic *beth-; or possibly from Anglo-French begger, from Old French begart (see beggar). The Old English word for "beg" was wædlian, from wædl "poverty." Of trained dogs, 1816.

As a courteous mode of asking (beg pardon, etc.), first attested c. 1600. To beg the question translates Latin petitio principii, and means "to assume something that hasn't been proven as a basis of one's argument," thus "asking" one's opponent to give something unearned, though more of the nature of taking it for granted without warrant.
began (v.): past tense of begin.
begat (v.): archaic past tense of beget.
beget (v.): Old English begietan "to get by effort, find, acquire, attain, seize" (class V strong verb, past tense begeat, past participle begeaton), from be- + get (v.). Sense of "to procreate" is from c. 1200. Related to Old High German pigezzan, Gothic bigitan "to get, obtain." Related: Begot; begotten.
begetter (n.): mid-15c., agent noun from beget.
beggar (n.): c. 1200, from Old French begart, originally a member of the Beghards, lay brothers of mendicants in the Low Countries, from Middle Dutch beggaert "mendicant," of uncertain origin, with pejorative suffix (see -ard). Compare Beguine. Early folk etymology connected the English word with bag. Form with -ar attested from 14c., but begger was more usual 15c.-17c. The feminine form beggestere is attested as a surname from c. 1300. Beggar's velvet was an old name for "dust bunnies." "Beggers should be no choosers" is in Heywood (1562).
beggar (v.): "reduce to poverty," mid-15c., from beggar (n.). Related: Beggared; beggaring. Figurative use by 1640s.
beggarly (adj.): 1520s, from beggar (n.) + -ly (1).
beggary (n.): late 14c.; see beg + -ary.
begin (v.): Old English beginnan "to begin, attempt, undertake," a rare word beside the more usual form onginnan (class III strong verb; past tense ongann, past participle ongunnen); from bi- (see be-) + West Germanic *ginnan, of obscure meaning and found only in compounds, perhaps "to open, open up" (compare Old High German in-ginnan "to cut open, open up," also "begin, undertake"), with sense evolution from "open" to "begin." Cognates elsewhere in Germanic include Old Frisian biginna "to begin," Middle Dutch beghinnen, Old High German beginnan, German beginnen, Old Frisian bijenna "to begin," Gothic duginnan.
beginner (n.): early 14c., "founder," agent noun from begin. Meaning "novice" is from late 15c. Beginner's luck is from 1897.
beginning (n.): late 12c., "time when something begins," from begin. Meaning "act of starting something" is from early 13c. The Old English word was fruma (see foremost).
begird (v.): Old English begyrdan; see be- + gird (v.).
begone (v.): late 14c., contracted from be (imperative) + gone.
begonia (n.): 1751, from French begonia (1706), named by Plumier for Michel Bégon (1638-1710), French governor of Santo Domingo (Haiti) and patron of botany, + abstract noun ending -ia.
begorra: 1839, antiquated Anglo-Irish form of expletive By God.
begotten (adj.): late 14c., past participle adjective from beget.
begrime (v.): 1530s, from be- + grime (n.). Related: Begrimed.
begrudge (v.): mid-14c., from be- + Middle English grucchen "to murmur" (see grudge). Related: Begrudged; begrudging; begrudgingly.
beguile (v.): early 13c., from be- + guile (v.). Related: Beguiled; beguiling.
beguiling (adj.): c. 1400, present participle adjective from beguile.
Beguine (n.): late 15c., from French béguine (13c.), Medieval Latin beguina, a member of a women's spiritual order said to have been founded c.1180 in Liege in the Low Countries. They are said to take their name from the surname of Lambert le Bègue "Lambert the Stammerer," a Liege priest who was instrumental in their founding, and it's likely the word was pejorative at first.

The order generally preserved its reputation, though it quickly drew imposters who did not; nonetheless it eventually was condemned as heretical. A male order, called Beghards founded communities by the 1220s in imitation of them, but they soon degenerated (compare Old French beguin "(male) Beguin," also "hypocrite") and wandered begging in the guise of religion; they likely were the source of the words beg and beggar, though there is disagreement over whether Beghard produced Middle Dutch beggaert "mendicant" or was produced by it.

Cole Porter's "Begin the Beguine" (1935) refers to a kind of popular dance of West Indian origin, from French colloquial béguin "an infatuation, boyfriend, girlfriend," earlier "child's bonnet," and before that "nun's headdress" (14c.), from Middle Dutch beggaert, ultimately the same word.
begun (v.): past participle of begin.
behalf (n.): c. 1300, behalve (with dative suffix), from Old English (him) be healfe "by (his) side," and on (his) healfe "on (his) side," from healfe "side" (see half).
behave (v.): early 15c., from be- intensive prefix + have in sense of "to have or bear (oneself) in a particular way, comport" (compare German sich behaben, French se porter). Cognate Old English compound behabban meant "to contain," and alternatively the modern sense of behave might have evolved from behabban via a notion of "self-restraint." Related: Behaved; behaving.
behavior (n.): late 15c., essentially from behave, but with ending from Middle English havour "possession," a word altered (by influence of have) from aver, noun use of Old French verb aveir "to have."
behavioral (adj.): 1927, in psychology, from behavior + -al (1).