'4-anisidine' ultimately derives from 'anisidine' (the name given to methoxy-substituted aniline derivatives). 'anisidine' traces back to Greek 'anison' (via Latin 'anisum'), where 'anison' meant 'anise' (the plant/seed), reflecting the association with anise oil or its aroma; the '4-' denotes the para (p-) position on the benzene ring.

'anisidine' entered chemical nomenclature in the 19th century as chemists named derivatives related to 'aniline' (itself named from 'anil', a term for indigo/plant dye). Over time the specific descriptor for the para isomer became standardized as 'p-anisidine' or '4-anisidine', and the modern systematic name '4-methoxyaniline' has also been adopted in IUPAC usage.

Initially the stem referred generally to compounds associated with anise-derived substances or aromas; it evolved to denote specifically an aniline derivative bearing a methoxy group, and '4-anisidine' now designates the para-methoxy-substituted aniline isomer.