Epistolary means written as a letter, or as a string of letters. The word you will hear in class is usually about books: an epistolary novel tells the whole story through letters (and sometimes diary pages) that the characters send each other. You never see the narrator standing outside; you only see what people wrote down. It is a school-and-book adjective, a little formal, not a word for everyday life. Though actually, people sometimes stretch it: a very long, careful email can feel “almost epistolary,” meaning it has that old letter-writing manner. There is also a rarer noun use for a book of church letters, but learners almost always meet the adjective.

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