'cation' originates from New Latin (from Greek elements), specifically from Greek components 'kata-' meaning 'down' and 'ion' meaning 'going', used to denote an ion that moves toward the cathode.

'cation' was coined in the 19th century in connection with 'cathode' (from Greek 'kathodos' meaning 'down way') and the Greek-derived suffix '-ion'; it entered scientific English as 'cation' and the plural form became 'cations'.

Initially it meant 'an ion moving toward the cathode' and, over time, it has come to be used more generally as 'a positively charged ion'.