Words related to *bhreg-
mid-15c., "instrument for crushing or pounding," from Middle Dutch braeke "flax brake," from breken "to break" (see break (v.)). The word was applied to many crushing implements, especially the tool for breaking up the woody part of flax to loosen the fibers. It also was applied to the ring through the nose of a draught ox. It was influenced in sense by Old French brac, a form of bras "an arm," thus the sense "a lever or handle," which was being used in English from late 14c., and "a bridle or curb" (early 15c.).
One or the other sense or a convergence of all of them yielded the main modern meaning "mechanical device for arresting the motion of a wheel," which is attested by 1772.
Old English bryce "a fracture, act of breaking," from Proto-Germanic *brukiz (source also of Old Frisian breke "a burst, crack, demolition (of a house)," Old Saxon bruki, Old High German bruh, Middle Dutch broke), a noun from *brekanan (source of Old English brecan "to shatter, burst; injure, violate, destroy, curtail;" see break (v.)). The English word was influenced by Old French cognate breche "breach, opening, gap," which is from Frankish or another Germanic source. Ultimately from PIE root *bhreg- "to break."
Figurative sense of "infraction, violation, a breaking of rules, etc." was in Old English. Meaning "opening made by breaking" is from late 14c. Meaning "rupture of friendly relations" is from 1570s. Breach of contract is from at least 1660s; breach of peace "violation of public order" is from 1670s; breach of promise (usually promise of marriage) is from 1580s.
Old English brecan "to divide solid matter violently into parts or fragments; to injure, violate (a promise, etc.), destroy, curtail; to break into, rush into; to burst forth, spring out; to subdue, tame" (class IV strong verb; past tense bræc, past participle brocen), from Proto-Germanic *brekanan (source also of Old Frisian breka, Dutch breken, Old High German brehhan, German brechen, Gothic brikan), from PIE root *bhreg- "to break."
Closely related to breach (n.), brake (n.1), brick (n.). The old past tense brake is obsolete or archaic; past participle is broken, but shortened form broke is attested from 14c. and was "exceedingly common" [OED] 17c.-18c.
Of bones in Old English. Formerly also of cloth, paper, etc. Meaning "escape by breaking an enclosure" is from late 14c. Intransitive sense "be or become separated into fragments or parts under action of some force" is from late 12c. Meaning "lessen, impair" is from late 15c. Meaning "make a first and partial disclosure" is from early 13c. Meaning "destroy continuity or completeness" in any way is from 1741. Of coins or bills, "to convert to smaller units of currency," by 1882. In reference to the heart from early 13c. (intransitive); to break (someone's) heart is late 14c.
Break bread "share food" (with) is from late 14c. To break ground is from 1670s as "to dig, plow," from 1709 in the figurative sense "begin to execute a plan." To break the ice "overcome the feeling of restraint in a new acquaintanceship" is from c. 1600, in reference to the "coldness" of encounters of strangers. Break wind first attested 1550s. To break (something) out (1890s) probably is an image from dock work, of freeing cargo before unloading it.
The ironic theatrical good luck formula break a leg (by 1948, said to be from at least 1920s) has parallels in German Hals- und Beinbruch "break your neck and leg," and Italian in bocca al lupo. Evidence of a highly superstitious craft (see Macbeth). According to Farmer & Henley, in 17c. the expression was used euphemistically, of a woman, "to have a bastard."
"bifurcated garment worn by men, covering the body and waist to the knees," c. 1200, a double plural (also breechen, and singular breech), from Old English brec "breeches," which already was plural of broc "garment for the legs and trunk," from Proto-Germanic *brokiz (source also of Old Norse brok, Dutch broek, Danish brog, Old High German bruoh, German Bruch, obsolete since 18c. except in Swiss dialect), perhaps from PIE root *bhreg- "to break." The etymological notion would be of a garment "forked" or "split." The singular breech survived into 17c., but the word is now always used in the plural.
The Proto-Germanic word is a parallel form to Celtic *bracca, source (via Gaulish) of Latin braca (source of French braies, Italian braca, Spanish braga). Some propose that the Germanic word group is borrowed from Gallo-Latin, others that the Celtic was from Germanic, but OED writes that the Proto-Germanic noun "has all the markings of an original Teutonic word."
Classical bracae were part of the characteristic garb of Gauls and Orientals; they were not worn by Greeks or Romans until the end of the republic. After 1 c. they came into use at first among military forces stationed in cold climates and were adopted generally toward the end of the empire, though they never seem to have been much in favor in Rome proper.
Expanded sense of "lower part of the body, part of the body covered by breeches, posterior" led to senses in childbirthing (1670s) and gunnery ("the part of a firearm behind the bore," 1570s). As the popular word for "trousers" in English, displaced in U.S. c. 1840 by pants. The Breeches Bible (Geneva Bible of 1560) so called on account of rendition of Genesis iii.7 (already in Wyclif) "They sewed figge leaues together, and made themselues breeches."