'balneation' originates from Latin, specifically the word 'balneatio', where 'balne-' (from Latin 'balneum') meant 'bath' (from Greek 'balaneion').

'balneation' changed from the Medieval/Latin word 'balneatio' (from Latin 'balneum' and Greek 'balaneion') and eventually became the modern English word 'balneation' through Late/Medieval Latin usage and later adoption into English.

Initially, it referred directly to a 'bath' or the practice of bathing, but over time it evolved to denote the act or process of bathing, especially in a therapeutic context ('the act of bathing' / 'therapeutic bathing').