break). The P.Gmc. word is a parallel form to Celt. *bracca, source (via Gaulish) of L. braca (cf. Fr. braies), and some propose that the Gmc. word group is borrowed from Gallo-Latin, others that the Celtic was from Germanic. Expanded sense of "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 Gen. iii.7 (already in Wyclif) "They sewed figge leaues together, and made themselues breeches."
breech"back part of a gun or firearm," 1570s, from sing. of
breeches (q.v.).