9 letters · 15 points in Scrabble
verb reveal unintentionally
verb deliver to an enemy by treachery
verb disappoint, prove undependable to; abandon, forsake
originEtymology tree English betray Proto-Indo-European *-onts Proto-Germanic *-ndz Proto-West Germanic *-andī Old English -ende Middle English -ynge English -ing English betraying From betray + -ing.
Etymology from Wiktionary, CC BY-SA 3.0