early 13c., "bent, curved, in a bent shape," past-participle adjective from crook (v.). In the figurative sense of "dishonest, false, treacherous, not straight in conduct" is from c. 1200. Related: Crookedly; crookedness.
1761, "winding or crooked line; anything full of twists and turns," mock Latin based on crank, etc.
early 14c., cromplen, crumplen, "press into irregular folds, rumple, wrinkle," also intransitive, "contract into wrinkles, shrink, shrivel," frequentative of crumpen "to curl up" (from Old English crump "bent, crooked"), from Proto-Germanic *krumbo- "to press, squeeze, compress" (source also of German krumm "crooked, warped"). Related: Crumpled; crumpling.
"involuntary and painful muscle contraction," late 14c., from Old French crampe (13c.), from a Frankish or other Germanic word (compare Old High German krapmhe "cramp, spasm," related to kramph "bent, crooked"), from Proto-Germanic *kramp-, forming many words for "bent, crooked," including, via French, crampon.
Writer's cramp is first attested 1842 as the name of a physical affliction of the hand, in discussions of translations of German medical papers (Stromeyer); also known as scrivener's palsy.