'autovalve' is a modern compound formed from the Greek-derived prefix 'auto-' meaning 'self' and the English word 'valve' (from Latin 'valva').

'valve' comes from Latin 'valva' meaning 'leaf of a door' or 'folding door'; it entered Middle English via Old French/Medieval Latin and developed into the modern English 'valve'. The compound 'autovalve' is a later technical formation combining 'auto-' with 'valve'.

Initially the elements meant 'self' + 'a folding door/leaf' (Latin 'valva'); over time the combined term came to mean 'a self-operating valve' in technical contexts.