1. a letter: formal, humorous"activists firing off angry epistles"
▪ a poem or other literary work in the form of a letter or series of letters.formal, humorous
▪ a book of the New Testament in the form of a letter from an Apostle: formal, humorous"St Paul's Epistle to the Romans"
▪ an extract from an Epistle (or another New Testament book not a Gospel) that is read in a church service.formal, humorous
Word OriginOld English, via Latin from Greek epistolē, from epistellein ‘send news’, from epi ‘upon, in addition’ + stellein ‘send’. The word was reintroduced in Middle English from Old French.