堅 — strict, hard, solid, tough, tight, reliable

彼かれの 決意けついは 堅かたいな。

His determination is firm.

彼女かのじょは 口くちを 堅かたく 結むすんだ。

She pressed her lips firmly together.

平安時代は中堅貴族であった。

The Kiyohara clan was a nobility of middle rank during the Heian period.