Source : Webster's Revised Unabridged Dictionary (1913)

Yearling \Year"ling\, n. [Year + -ling.]
   An animal one year old, or in the second year of its age; --
   applied chiefly to cattle, sheep, and horses.

Yearling \Year"ling\, a.
   Being a year old. ``A yearling bullock to thy name small
   smoke.'' --Pope.

Source : WordNet®

yearling
     n 1: a young child [syn: {toddler}, {tot}, {bambino}]
     2: a racehorse considered one year old until the second Jan. 1
        following its birth
     3: an animal in its second year