catarrh: [16] Etymologically, catarrh is ‘something that flows down’. It comes via French catarrhe and late Latin catarrhus from Greek katárrhous, a derivative of the verb katarrhein, a compound formed from the prefix katá- ‘down’ (as in cataract) and the verb rhein ‘flow’ (a relative of English rheumatism and stream). => diarrhoea, rheumatism, stream[catarrh etymology, catarrh origin, 英语词源]