noun
perfect role; well-suited role
Refers to a role in a play, film, or other performance that fits an actor perfectly, as if they were born to play it. Also used figuratively for any task or position that suits someone exceptionally well.
彼はその映画で、まさにはまり役を演じた。
He played a perfect role for him in that movie.
この仕事は彼女にとってはまり役だと思う。
I think this job is a perfect fit for her.
Rarely used kanji form; the kanji 填 is not common in modern Japanese.
適役 also means a suitable role, but はまり役 emphasizes a perfect, almost destined fit, often with a nuance of enthusiasm.
Compound of はまり (continuative form of はまる 'to fit perfectly') + 役 (role). The exact historical derivation is uncertain, but the word likely emerged from theatrical or entertainment contexts.