nature of one's position; what one's role entails
Refers to the inherent duties, expectations, or character of a particular role or position, often used when discussing whether something is suitable or appropriate for that role.
役向きに合った行動をとるべきだ。
You should act in a way that suits your position.
彼は
He understands the nature of his role.
Compound of 役 (role, duty) and 向き (direction, suitability). The exact historical derivation is uncertain, but the word literally suggests 'the direction or suitability of a role'.