betray

v.

1. To deliver into the hands of an enemy

   play false, break faith (with), inform on, inform against, turn in, commit treason, turn informer, delude, break one's promise, be false to, be false-hearted to, be disloyal to, go over to the enemy, trick, let down, disappoint, deceive, sell down the river*, play Judas*, give the Judas kiss to*, double-cross*, deliver up*, sell out*, stab in the back*, bite the hand that feeds one*, cross up*, turn state's evidence; see also deceive, inform 2.

   Antonyms support*, adhere*, stand firm.

2. To lead astray

   seduce, misguide, corrupt; see seduce.

3. To reveal

   divulge, disclose, uncover, make known; see reveal 1. See syn. study at deceive, reveal.