Defiant \De*fi"ant\, a. [Cf. F. d['e]fiant, p. pr. of d['e]fier. See {Defy}.] Full of defiance; bold; insolent; as, a defiant spirit or act. [1913 Webster] In attitude stern and defiant. --Longfellow. -- {De*fi"ant*ly}, adv. -- {De*fi"ant*ness}, n. [1913 Webster]