epistolium
From LSJ
ἐπ' αὐτὸν ἥκεις τὸν βατῆρα τῆς θύρας → you've come to the crux of the matter, come to the point, hit the nail on the head, you've come to the very threshold of the door, you are come to the very threshold of the door, you've arrived at the truth of the matter
Latin > English
epistolium epistolii N N :: note, short letter
Latin > English (Lewis & Short)
ĕpīstŏlĭum: ii, n., = ἐπιστόλιον,
I a short letter, note, Cat. 68, 2.
Latin > French (Gaffiot 2016)
ĕpistŏlĭum,¹⁶ ĭī, n. (ἐπιστόλιον), courte lettre, billet : Catul. 68, 2 || petite pièce de vers : Apul. Apol. 6.
Latin > German (Georges)
epistolium, iī, n. (επιστόλιον), das Briefchen, Catull. 68, 2. Apul. apol. 6 u. 79; vgl. Gloss. II, 311, 19.
Latin > Chinese
epistolium, ii. n. :: 便札