'gymnospermous' is formed in English from the New Latin word 'Gymnospermae' / 'gymnosperm' plus the adjectival suffix '-ous'. The New Latin 'gymnosperm' derives from Greek 'gymnos' meaning 'naked' and 'sperma' meaning 'seed'.

The Greek elements 'gymnos' + 'sperma' produced the New Latin botanical term 'Gymnospermae' (used for the group of 'naked-seeded' plants), which entered English as 'gymnosperm' and later gave rise to the adjective 'gymnospermous' by adding '-ous'.

Originally meant 'having naked seeds' (literally 'naked-seeded'); this core meaning has been retained and is still used to describe plants whose seeds are not enclosed in an ovary.