verb

1. To deliver into the hands of an enemy by treachery or fraud, in violation of trust; to give up treacherously or faithlessly.

   “an officer betrayed the city”

2. To prove faithless or treacherous to, as to a trust or one who trusts; to be false to; to deceive.

   “My eyes have been betraying me since I turned sixty.”

3. To violate the confidence of, by disclosing a secret, or that which one is bound in honor not to make known.

Synonyms: sell