verb/tʁa.iʁ/
to betray; to give away, to reveal
“Ils ne doivent pas trahir la confiance que nous avons placée en eux en commettant des actes de violence aveugle.” — They mustn't betray the trust we've placed in them by committing indiscriminate acts of violence.
Inherited from Middle French trahir < Old French traïr, itself from Latin trādō 'betray'.