What is "patter song"

The patter song is characterised by a moderately fast to very fast tempo with a rapid succession of rhythmic patterns in which each syllable of text corresponds to one note. It is a staple of comic opera, especially Gilbert and Sullivan, but it has also been used in musicals and elsewhere.

The lyric of a patter song generally features tongue-twisting rhyming text, with alliterative words and other consonant or vowel sounds that are intended to be entertaining to listen to at rapid speed. The musical accompaniment is lightly orchestrated and fairly simple, to emphasise the text. The song is often intended as a showpiece for a comic character, usually a bass or baritone. The singer should be capable of excellent enunciation, to show the song to maximum effect.