'phalliform' originates from New Latin, specifically the word 'phalliformis,' where 'phall-' comes from Greek 'phallos' meaning 'phallus' and '-form' comes from Latin 'forma' meaning 'shape'.

'phalliform' changed from New Latin 'phalliformis' and entered English in the 19th century as the adjective 'phalliform'.

Initially, it meant 'having the shape of a phallus', and over time it has retained this specific descriptive meaning in scientific and descriptive contexts.