na-adjective, noun
Describes a strong, unyielding character, will, or attitude; often used in literary or formal contexts. Can also refer to physical robustness.
彼の剛強な意志はどんな困難にも負けなかった。
His strong will never yielded to any hardship.
剛強な体を持つ戦士だった。
He was a warrior with a robust body.