Meaning

noun a slight indication

noun evidence that helps to solve a problem

verb roll into a ball

originVariant of clew (“a ball of thread or yarn”), from Middle English clew, clewe, clowe, clue, clwe, clyw, clywe, from Old English clēowen, clīewen, clīowen, clīwen, clȳwe, clȳwen (“ball, sphere; skein”), from Proto-West Germanic *kliuwīn (“ball, clump”), from Proto-Germanic *kliuwīną, *klewô (“bale, ball, clump, mass”), from Proto-Indo-European *glew- (“to ball up, clump together; lump, swelling”).…

Etymology from Wiktionary, CC BY-SA 3.0