lactam

noun Chemistry.

1. any of a group of cyclic amides characterized by the NHCO group, derived from aminocarboxylic acids by the intramolecular elimination of water from the amino and carboxylic groups.

noun

1. chem any of a group of inner amides, derived from amino acids, having the characteristic group -CONH-

n.

1. An amide formed from amino carboxylic acids containing a keto group in a ring configuration, as seen in purines, pyrimidines, and antibiotics. It is tautomeric to lactim.