Etymology
From Middle English thille, thylle, from Old English þille (“board; floorboard; plank; stake; pole”), from Proto-West Germanic *þilljā, from Proto-Germanic *þiljǭ (“board; floorboard; deck”), from Proto-Indo-European *tel- (“plank; board”). Cognate with Dutch deel, German Low German Deel (> English deal (“plank”)), German Diele, Swedish tilja, Icelandic þilja. Akin to English theal (“board; plank”). Doublet of deal (etymology 3).