noun
Refers to the finger joints, especially in contexts like martial arts, anatomy, or casual speech.
彼はナックルで相手を殴った。
He punched his opponent with his knuckles.
noun
knuckleball
Baseball term for a pitch with little spin; often used in the full form ナックルボール.
See also: ナックルボール
彼のナックルは打ちにくい。
His knuckleball is hard to hit.