Peptide which is posttranslationally modified by C-terminal amidation. The amino acid to be modified is almost always followed by a glycine, which provides the amide group. In a first reaction step the glycine is oxidized to form alpha-hydroxy-glycine. The oxidized glycine cleaves into the C-terminally amidated peptide and an N-glyoxylated peptide. C-terminal amidation is essential to the biological activity of many neuropeptides and hormones. In a few cases alpha-oxidative cleavage of an amino acid other than glycine has been observed. All such cases are additionally annotated with the word "atypical" in the feature description.