The Collaborative International Dictionary of English v.0.48:

Acetamide \Ac`et*am"ide\, n. [Acetyl + amide.] (Chem.)
   A white crystalline solid, from ammonia by replacement of an
   equivalent of hydrogen by acetyl.
   [1913 Webster]

WordNet (r) 3.0 (2006):

acetamide
    n 1: a colorless solid amide of acetic acid used as a solvent
         and in the synthesis of organic compounds [syn:
         acetamide, ethanamide]