'N-phenylamino' is a compound formed in modern chemical nomenclature from three elements: the letter 'N' (the chemical symbol for nitrogen), 'phenyl' (a radical name used in organic chemistry), and 'amino' (from 'amine', referring to an -NH- or -NH2 group).

'N-' derives from the chemical symbol 'N' for nitrogen; 'phenyl' was coined in 19th-century organic chemistry to name the C6H5– radical derived from benzene; 'amino' comes from 'amine', ultimately from 'ammonia' and its derivatives. These parts were concatenated following systematic naming conventions to form 'N-phenylamino'.

Initially, the separate elements referred to the atom ('N'), the phenyl radical ('phenyl'), and the amine-derived group ('amino'); combined, they now denote a specific substitution pattern (an amino group attached to a phenyl on nitrogen) used in systematic chemical names.