de ‧ fi ‧ ant /dɪˈfaɪənt/ BrE AmE adjective
[ Date: 1500-1600 ; Language: French ; Origin: défiant , present participle of défier ; ⇨ ↑ defy ]
clearly refusing to do what someone tells you to do:
Mark smashed a fist on the desk in a defiant gesture.
—defiantly adverb