was disloyal (verb) stab in the back: attack unsuspecting person
Sinonime: abandon, backstab, be disloyal, be unfaithful,
betray, break promise, commit treason,
cross,
deceive, double-cross, doublecross,
finger*, go back on, inform on, play Judas, sell down the river, sell down the river, sell out,
trick, turn in, turn informer, turn traitor