1. A letter, especially a formal one. See Synonyms at letter.
2. A literary composition in the form of a letter.
3. Epistle Bible
a. One of the letters included as a book in the New Testament.
b. An excerpt from one of these letters, read as part of a religious service.
[Middle English epistel, from Old French epistle, from Latin epistola, from Greek epistolē, from epistellein, to send a message to : epi-, epi- + stellein, to send; see stel- in the Appendix of Indo-European roots.]
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