μαυροπόδαρος

From LSJ

κέρκος τῇ ἀλώπεκι μαρτυρεῖ → you can tell a fox by its tail, small traits give the clue to the character of a person

Source

Greek Monolingual

μαυροπόδαρος, -η, -ον (Μ)
αυτός που έχει μαύρα πόδια.