noun
tough outside, soft inside; faint-hearted person acting brave
Describes a person who appears strong or brave outwardly but is actually gentle or timid. Often used to characterize someone who puts on a brave front.
彼は外剛内柔で、強がっているけど本当は優しい。
He is tough on the outside but soft at heart; he acts tough but is actually kind.
外剛内柔な人ほど、内面の弱さを隠そうとする。
The more a person is faint-hearted pretending to be brave, the more they try to hide their inner weakness.
A yojijukugo composed of 外 (outside), 剛 (strong), 内 (inside), 柔 (soft). The exact origin is uncertain, but it follows a common Chinese-derived four-character pattern contrasting outward appearance with inner nature.