The Collaborative International Dictionary of English v.0.48:

Amide \Am"ide\ (?; 277), n. [Ammonia + -ide.] (Chem.)
   A compound formed by the union of amidogen with an acid
   element or radical. It may also be regarded as ammonia in
   which one or more hydrogen atoms have been replaced by an
   acid atom or radical.
   [1913 Webster]

   Acid amide, a neutral compound formed by the substitution
      of the amido group for hydroxyl in an acid.
      [1913 Webster]

WordNet (r) 3.0 (2006):

amide
    n 1: any organic compound containing the group -CONH2