(1):

(n.) A youth beloved by Venus for his beauty. He was killed in the chase by a wild boar.

(2):

(n.) A preeminently beautiful young man; a dandy.

(3):

(n.) A genus of plants of the family Ranunculaceae, containing the pheasant's eye (Adonis autumnalis); - named from Adonis, whose blood was fabled to have stained the flower.