12 letters · 25 points in Scrabble
originEtymology tree Proto-Indo-European *kʷetwóresder. Proto-Indo-European *kʷetwr̥- Proto-Italic *kʷetru- Latin quadri-bor. English quadri- English -valent English quadrivalent From quadri- + -valent.
Etymology from Wiktionary, CC BY-SA 3.0