Amides of carboxylic acids, having the structure RC(=O)NR2. The term is used as a suffix in systematic name formation to denote the –C(=O)NH2 group including its carbon atom.
PAC, 1995, 67, 1307 (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1326