guile n.

mid-12c., from Old French guile "deceit, wile, fraud, ruse, trickery," probably from Frankish *wigila "trick, ruse" or a related Germanic source, from Proto-Germanic *wih-l- (source also of Old Frisian wigila "sorcery, witchcraft," Old English wig "idol," Gothic weihs "holy," German weihen "consecrate"), from PIE root *weik- (2) "consecrated, holy."