力ちからこぶ

noun

biceps bulge; flexed biceps

Refers to the visible bulge of the biceps when flexed; often used in the phrase 力こぶを作る (make a muscle).

• 彼かれは力ちからこぶを作つくって見みせた。

  He flexed his biceps to show off.

noun

zeal; effort; enthusiasm

Used almost exclusively in the set phrase 力こぶを入れる, meaning to put in extra effort or enthusiasm into something.

See also: 力こぶを入れる

• 彼かれは仕し事ごとに力ちからこぶを入いれている。

  He is putting a lot of effort into his work.