sermon: [12] Latin sermō meant simply ‘talk, conversation, discourse’, but by the time it reached English via Anglo-Norman sermun it had narrowed down to an ‘address given from a pulpit on a religious topic’. It is not clear what its ultimate ancestry is, but probably the favourite candidate as its source is the Indo-European base *swer-, *swar-, which gave English answer and swear. [sermon etymology, sermon origin, 英语词源]