'azophenylene' originates from Modern chemical English, specifically from the combining prefix 'azo-' (from French 'azote', ultimately from Greek elements where 'a-' meant 'not' and 'zōē' meant 'life') and 'phenylene' (from 'phenyl' + '-ene', with 'phenyl' ultimately from Greek roots related to 'phainō').

'azophenylene' changed from earlier descriptive chemical phrases such as 'azo-phenyl(ene)' used in 19th-century chemical literature and eventually became the consolidated modern English term 'azophenylene'.

Initially, it referred generically to an azo-related phenyl descriptor in early chemical descriptions, but over time it evolved into its current specific meaning of a phenylene unit linked by an azo (-N=N-) bond or a compound containing such a unit.