Betrayal/bɪ'treɪəl/ - cruel or dishonest behaviour towards someone who trusts you
Ru: предательство
Глагол betray означает не только предавать, но и выдавать:
Betray secret - выдать секретBetray + emotion - выдавать какую-либо эмоцию
Her face was calm, but her hands betrayed her nervousness. Maybe it was a bad idea to betray this secret.
Manga: Kaguya-sama: Love is War