ἐπιμύθιον

From LSJ

ἐν ταῖς ἀνάγκαις χρημάτων κρείττων φίλος → it is better in times of need to have friends rather than money, a friend in need is a friend indeed (Menander, Sententiae monostichoi 143)

Source

French (Bailly abrégé)

ου (τό) :
affabulation, morale d'une fable ou d'un récit.
Étymologie: ἐπί, μῦθος.

Russian (Dvoretsky)

ἐπιμύθιον: (ῡ) τό послесловие к сказке, т. е. нравоучение, мораль Luc.