Source : Webster's Revised Unabridged Dictionary (1913)

Snowcap \Snow"cap`\, n. (Zo["o]l.)
   A very small humming bird ({Microch[ae]ra albocoronata})
   native of New Grenada.

   Note: The feathers of the top of the head are white and
         snining, the body blue black with a purple and bronzy
         luster. The name is applied also to {Microch[ae]ra
         parvirostris} of Central America, which is similar in
         color.

Source : WordNet®

snowcap
     n : a covering of snow (as on a mountain peak)