defiance (n.)

c. 1300, from Old French desfiance "challenge, declaration of war," from desfiant, present participle of desfier "to challenge, defy, provoke; renounce (a belief), repudiate (a vow, etc.)," from Vulgar Latin *disfidare "renounce one's faith," from Latin dis- "away" (see dis-) + fidus "faithful" (from PIE root *bheidh- "to trust, confide, persuade").