betray

verb

1
give away information about somebody
He told on his classmate who had cheated on the exam
2
cause someone to believe an untruth
The insurance company deceived me when they told me they were covering my house
3
reveal unintentionally
Her smile betrayed her true feelings
4
disappoint, prove undependable to; abandon, forsake
His sense of smell failed him this time
His strength finally failed him
5
deliver to an enemy by treachery
Judas sold Jesus
The spy betrayed his country
6
be sexually unfaithful to one's partner in marriage
She cheats on her husband
Might her husband be wandering?

Also useful for “betray”:Unscrambler— Rearrange the letters in “betray”