εὐπαθεῖν
From LSJ
ἐξ ὀνύχων λέοντα τεκμαίρεσθαι → judge by the claws, judge by a slight but characteristic mark, small traits give the clue to the character of a person, deduce something from a small indication, identify a lion from its claws
Greek > English (Woodhouse Verbs Reversed)
(see also: εὐπαθέω) be comfortable, be in one's element, enjoy oneself