Lewis Short
(adjective) : ĕpistŭlāris (epistol-, v. epistula
* Init.), e, epistula, of or belonging to a letter, epistolary.
* Adj.: chartae,letter-paper,Mart. 14, 11in lemm.;Dig. 33, 9, 3, § 10: colloquium,epistolary,Aug. Ep. ad Marcell. 5.
* Subst.: epistŭlāris, is, f., a messenger of the Eagle of Jupiter: epistularis tua,Mart. Cap. 9, § 896.—Plur.: epistulāres, ium, m., state secretaries, Cod. Th. 6, 30, 7.
Charlton T. Lewis, Charles Short, A Latin Dictionary