- To deliver into the hands of an enemy by treachery or fraud, in violation of trust; to give up treacherously or faithlessly; as, an officer betrayed the city.
- To prove faithless or treacherous to, as to a trust or one who trusts; to be false to; to deceive; as, to betray a person or a cause.
- To violate the confidence of, by disclosing a secret, or that which one is bound in honor not to make known.
- To disclose or discover, as something which prudence would conceal; to reveal unintentionally; to bewray.
- To mislead; to expose to inconvenience not foreseen to lead into error or sin.
- To lead astray, as a maiden; to seduce (as under promise of marriage) and then abandon.
- To show or to indicate; -- said of what is not obvious at first, or would otherwise be concealed.
The above text is a snippet from Wiktionary: betray
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