Source : Webster's Revised Unabridged Dictionary (1913)

Nappy \Nap"py\, a. [From 1st {Nap}.]
   1. Inclined to sleep; sleepy; as, to feel nappy.

   2. Tending to cause sleepiness; serving to make sleepy;
      strong; heady; as, nappy ale. [Obs.] --Wyatt.

Nappy \Nap"py\, a. [From 3d {Nap}.]
   Having a nap or pile; downy; shaggy. --Holland.

Nappy \Nap"py\, n.; pl. {Nappies}. [OE. nap, AS. hn[ae]p cup,
   bowl. See {Hanaper}.]
   A round earthen dish, with a flat bottom and sloping sides.
   [Written also {nappie}.]

Source : WordNet®

nappy
     adj : in small tight curls [syn: {crisp}, {frizzly}, {frizzy}, {kinky}]
     n : garment consisting of a folded cloth drawn up between the
         legs and fastened at the waist; worn by infants to catch
         excrement [syn: {diaper}, {napkin}]
     [also: {nappiest}, {nappier}]