'cholangiocholecystitis' originates from New Latin/Modern medical formation, specifically from the combining forms 'cholangio-' (from Greek 'chole' meaning 'bile' and 'angeion' meaning 'vessel'), 'cholecyst-' (from Greek 'kystis' meaning 'bladder'), and the suffix '-itis' (from Greek 'itēs' meaning 'inflammation').

'cholangiocholecystitis' was formed in medical New Latin/Modern English by compounding Greek-derived combining forms ('cholangio-' + 'cholecyst-') with the classical medical suffix '-itis' to indicate inflammation; it entered English usage through medical Latin terminology.

Initially it referred specifically to inflammation involving bile vessels and the gallbladder in medical descriptions, and it has retained that same precise clinical meaning in modern usage.