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.
Composed of 剛 (strong, firm) and 強 (strong, powerful). The exact historical derivation is uncertain, but the combination naturally conveys strength and firmness.