Tempestuous \Tem*pes"tu*ous\, a. [L. tempestuous: cf. OF. tempestueux, F. temp[^e]tueux.] Of or pertaining to a tempest; involving or resembling a tempest; turbulent; violent; stormy; as, tempestuous weather; a tempestuous night; a tempestuous debate. -- {Tem*pes"tu*ous*ly}, adv. -- {Tem*pes"tu*ous*ness}, n. They saw the Hebrew leader, Waiting, and clutching his tempestuous beard. --Longfellow.