Source : Webster's Revised Unabridged Dictionary (1913)

Amygdalin \A*myg"da*lin\, n. (Chem.)
   A glucoside extracted from bitter almonds as a white,
   crystalline substance.

Source : WordNet®

amygdalin
     n : a bitter cyanogenic glucoside extracted from the seeds of
         apricots and plums and bitter almonds