betrayal

UK: /bɪˈtreɪəl/ US: /bɪˈtreɪəl/

WordReference Random House Learner's Dictionary of American English © 2025

be•tray•al /bɪˈtreɪəl/   n. 

1. [uncountable] betraying or being betrayed:
   At that point we feared betrayal more than anything else.
2. an act of betraying or being betrayed:
   [countable] When he failed to support her, she took it as a betrayal.

WordReference Random House Learner's Dictionary of American English © 2025

be•tray /bɪˈtreɪ/   v. [~ + object]

1. to deliver or expose to an enemy by treachery:
   [~ + object (+ to + object)] Benedict Arnold tried to betray his country to the enemy.
2. to be unfaithful or disloyal to:
   to betray one's friends.
3. to reveal or make known (a secret given in confidence):
   to betray a plan.
4. to reveal unconsciously (something a person would prefer to hide):
   The nervousness on her face betrays her insecurity.
5. to be unfaithful to (someone) by having sexual relations with someone else:
   He vowed never to betray his wife again.

be•tray•er, n. [countable]

WordReference Random House Unabridged Dictionary of American English © 2025

be•tray  (bi trā′), v.t. 

1. to deliver or expose to an enemy by treachery or disloyalty:
   Benedict Arnold betrayed his country.
2. to be unfaithful in guarding, maintaining, or fulfilling:
   to betray a trust.
3. to disappoint the hopes or expectations of;
   be disloyal to:
   to betray one's friends.
4. to reveal or disclose in violation of confidence:
   to betray a secret.
5. to reveal unconsciously (something one would preferably conceal):
   Her nervousness betrays her insecurity.
6. to show or exhibit;
   reveal;
   disclose:
   an unfeeling remark that betrays his lack of concern.
7. to deceive, misguide, or corrupt:
   a young lawyer betrayed by political ambitions into irreparable folly.
8. to seduce and desert.

• Latin trādere to betray. See traitor
• Old French trair
• Middle English bitraien, equivalent. to bi- be- + traien 1200–50

be•tray′al, n. 
be•tray′er, n. 
Synonyms

• 4. bare, expose, tell, divulge.
• 6. display, manifest, expose, uncover.

Antonyms

• 4, 6. hide, conceal.