εὐκαμπτής

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

French (Bailly abrégé)

ής, ές :
1 bien courbé, bien recourbé;
2 qui se recourbe facilement, souple, flexible.
Étymologie: εὖ, κάμπτω.