actor's temperament; theatrical disposition
Refers to the stereotypical personality traits associated with actors: emotional, dramatic, or attention-seeking.
He has an actor's temperament and uses exaggerated gestures even when talking.
職人気質 refers to a craftsman's temperament (dedicated, meticulous), while 役者気質 is specifically about an actor's dramatic or emotional disposition.
Compound of 役者 (actor) and 気質 (temperament, disposition).