Old English þwong, þwang "narrow strip of leather" (used as a cord, band, strip, etc.), from Proto-Germanic *thwang- (source also of Old Norse þvengr), from PIE root *twengh- "to press in on, to restrain" (source also of Old English twengan "to pinch, squeeze"). As a kind of sandal, first attested 1965; as a kind of bikini briefs, 1990.
1540s, "a pinch, a nipping," from obsolete verb twinge "to pinch, tweak," from Old English twengan "to pinch," from Proto-Germanic *twangjan (source also of Old Frisian thwinga, Old Norse þvinga, Danish tvinge, Dutch dwingen, Old High German thwingan, German zwingen "to compel, force"), from PIE *twengh- "to press in on" (see thong). Meaning "sharp, sudden minor pain" is recorded from c. 1600. Figurative sense (with reference to shame, remorse, etc.) is recorded from 1620s.
"penis," 1933, slang, probably from whangdoodle, an earlier term for "gadget, thing for which the correct name is not known." Many such words (thingy, dingus, etc.) have been used in slang for "penis," not because the actual name was unknown, but because it was unmentionable. Another possibility is that the slang word is a variant of whang "large, thick slice" (1630s), which earlier was used in the sense of "thong" (1530s) and is itself a variant of thwang, an alternative form of thong (see thong). In Old English, wang meant "cheek, jaw," hence wangtoð "cheek-tooth, molar."
also laniard, "small rope or cord used aboard ships," alternative spelling (influenced by nautical yard (2) "long beam used to support a sail") of Middle English lainer, "thong for fastening parts of armor or clothing" (late 14c.), from Old French laniere "thong, lash, strap of leather," from lasniere (12c., from lasne "strap, thong"), apparently altered (by metathesis and influence of Old French las "lace") from nasliere (nasle), from Frankish *nastila or some other Germanic source, from Proto-Germanic *nastila- (source also of Old High German, Old Saxon nestila "lace, strap, band," German nestel "string, lace, strap"), from PIE root *ned- "to knot."
small rope used on ships, mid-15c., from Old French brail, earlier braiel "belt, leather thong" (in falconry), from Latin bracale "waistbelt," from bracæ "breeches" (plural, see breeches).
"strap or thong of a sandal or shoe," late 14c., lachet, from Old French lachet, variant of lacet, diminutive of las, laz "noose, string, cord, tie" (see lace (n.)). Spelling altered perhaps by influence of latch.
"a flogging," 1809, from hide (n.1), perhaps in reference to a whip or thong made of animal hide, or of "tanning" someone's "hide." Old English had hyde ðolian "to undergo a flogging," and hydgild "fine paid to save one's skin (from a punishment by flogging)." The English expression a hiding to nothing (by 1905) referred to a situation where there was disgrace in defeat and no honor in victory.
c. 1200, "a whip used for inflicting pain or punishment, a lash used for torture," from Anglo-French scorge, escorge, back-formation from Old French scurge, eschurge "a whip, scourge, thong," from escorgier "to whip," which is from Vulgar Latin *excorrigiare. This is a compound of Latin ex- "out, off," or here perhaps intensive, (see ex-) + corrigia "thong, shoelace," in Late Latin "rein," with sense extension here to "whip." This is probably [Barnhart] from a Gaulish word related to Old Irish cuimrech "fetter," from PIE root *reig- "to bind" (see rig (v.)).
Figurative use is from late 14c., biblical, "a punishment, a punitive infliction;" also "one who or that which scourges or destroys." Scourge of God (Latin flagellum Dei), a title given by later generations to Attila the Hun (406-453 C.E.), is attested from late 14c. (Goddes scourge).
c. 1300, "thong for holding a dog or hound," from Old French lesse, laisse "hound's leash," ultimately from Latin laxus "loose" (see lax), perhaps via noun use of fem. form laxa. The notion seems to be of a string loosely held. Figurative sense attested from early 15c. The meaning "a set of three, three creatures of a kind" is from early 14c., originally in sporting language and especially of greyhounds, foxes, bucks, or hares.