'electrolyte' originates from New Latin/Greek elements: 'electro-' from Greek 'elektron' meaning 'amber' (later associated with 'electricity') and '-lyte' from Greek 'lytos' meaning 'able to be loosened' (from the verb 'lyein', 'to loosen').

'electrolyte' was formed in the 19th century from the combining form 'electro-' (relating to electricity) and the suffix '-lyte' (from Greek), appearing in scientific literature to name substances involved in electrolysis and related processes.

Initially it referred broadly to substances involved in electrolysis (substances that could be decomposed by electric current); its modern usage more commonly denotes ionic substances or solutions that conduct electricity and, in biological contexts, the dissolved mineral ions in bodily fluids.