Source : Webster's Revised Unabridged Dictionary (1913)

Somnolent \Som"no*lent\, a. [F. somnolent, L. somnolentus, from
   somnus sleep, akin to Gr. ?, Skr. svapna sleep, dream, svap
   to sleep, Icel. sofa, AS. swefn sleep. Cf. {Hypnotic},
   {Somnambulism}, {Soporific}.]
   Sleepy; drowsy; inclined to sleep. -- {Som"no*lent*ly}, adv.

         He had no eye for such phenomens, because he had a
         somnolent want of interest in them.      --De Quincey.

Source : WordNet®

somnolent
     adj : inclined to or marked by drowsiness; "slumberous (or
           slumbrous) eyes"; "`slumbery' is archaic"; "the sound
           had a a somnolent effect" [syn: {slumberous}, {slumbery},
            {slumbrous}]