1. A daring; a challenge to fight; invitation to combat; a call to an adversary to encounter, if he dare. Goliath bid defiance to the army of Israel.
2. A challenge to meet in any contest; a call upon one to make good any assertion or charge; an invitation to maintain any cause or point.
3. Contempt of opposition or danger; a daring or resistance that implies the contempt of an adversary, or of any opposing power. Men often transgress the law and act in defiance of authority.