'hydrobiologist' originates from Greek, specifically the words 'hydro' meaning 'water' and 'bios' meaning 'life', combined with 'logia' meaning 'study of'.

'hydrobiologist' evolved from the combination of Greek roots 'hydro-' and 'bio-' with the suffix '-logist', forming the modern English term.

Initially, it meant 'one who studies water life', and this meaning has largely remained the same in modern usage.