Source : Webster's Revised Unabridged Dictionary (1913)

Riant \Ri`ant"\, a. [F. riant, p. pr. of rire to laugh, L.
   ridere.]
   Laughing; laughable; exciting gayety; gay; merry; delightful
   to the view, as a landscape.

         In such cases the sublimity must be drawn from the
         other sources, with a strict caution, howewer, against
         anything light and riant.                --Burke.

Source : WordNet®

riant
     adj : showing or feeling mirth or pleasure or happiness; "laughing
           children" [syn: {laughing(a)}]