Epistle(n.) A writing directed or sent to a person or persons; a written communication; a letter; -- applied usually to formal, didactic, or elegant letters.
Epistle(n.) One of the letters in the New Testament which were addressed to their Christian brethren by Apostles.
Epistle(v. t.) To write; to communicate in a letter or by writing.
Epistler(n.) A writer of epistles, or of an epistle of the New Testament.
Epistler(n.) The ecclesiastic who reads the epistle at the communion service.

Words within epistle