Source : Webster's Revised Unabridged Dictionary (1913)

Riotous \Ri"ot*ous\, a. [OF. rioteux.]
   1. Involving, or engaging in, riot; wanton; unrestrained;
      luxurious.

            The younger son . . . took his journey into a far
            country, and there wasted his substance with riotous
            living.                               --Luke xv. 13.

   2. Partaking of the nature of an unlawful assembly or its
      acts; seditious. -- {Ri"ot*ous*ly}, adv. --
      {Ri"ot*ous*ness}, n.

Source : WordNet®

riotously
     adv 1: in a tumultuous and riotous manner; "the crowd was
            demonstrating tumultuously" [syn: {tumultuously}]
     2: in an exuberant manner; "the exuberantly baroque decoration
        of the church" [syn: {exuberantly}]