'antidiuretic' is formed from the prefix 'anti-' (from Greek, meaning 'against') combined with 'diuretic' (from New Latin/Modern medical usage), where 'diuretic' derives ultimately from Greek elements related to urine.

'diuretic' comes via New Latin/Modern medical Latin from Greek roots (related to 'diourein', to urinate); the compound 'antidiuretic' was created in English by adding the prefix 'anti-' to denote an agent opposing diuresis, becoming established in medical usage in the 19th–20th century.

Initially built to mean 'against diuresis' (i.e., opposing urine production); its usage has remained focused on substances or hormones that reduce urine output, now commonly naming specific hormones (e.g., antidiuretic hormone) and drugs.