8 letters · 17 points in Scrabble
noun a toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion
originEtymology tree Proto-Indo-European *gēw- Proto-Indo-European *gugāder. Proto-Germanic *kuggōder. Old Norse *koggrbor. Middle English cogge English cog Proto-Indo-European *kʷel- Proto-Indo-European *kʷekʷléh₂ Proto-Germanic *hweulō Old English hwēol Middle English whel English wheel English cogwheel From cog + wheel.
Etymology from Wiktionary, CC BY-SA 3.0