Source : Webster's Revised Unabridged Dictionary (1913)

Mariposa lily \Ma`ri*po"sa lil`y\ [Sp. mariposa a butterfly + E.
   lily. So called from the gay apperance of the blossoms.]
   (Bot.)
   One of a genus ({Calochortus}) of tuliplike bulbous herbs
   with large, and often gaycolored, blossoms. Called also
   {butterfly lily}. Most of them are natives of California.

Source : WordNet®

mariposa lily
     n : any of several plants of the genus Calochortus having
         tulip-shaped flowers with 3 sepals and 3 petals;
         southwestern United States and Mexico [syn: {mariposa}, {mariposa
         tulip}]