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.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.