Source : Webster's Revised Unabridged Dictionary (1913)

Birdie \Bird"ie\, n.
   A pretty or dear little bird; -- a pet name. --Tennyson.

Source : WordNet®

birdie
     n 1: (golf) a score of one stroke under par on a hole
     2: badminton equipment consisting of a ball of cork or rubber
        with a crown of feathers [syn: {shuttlecock}, {bird}, {shuttle}]
     v : to shoot in one stroke under par