expression, ichidan verb
show off one's manliness; act like a real man
Used when a man demonstrates strength, courage, or reliability, often in a situation where he wants to prove himself. Can be used seriously or with a slightly ironic tone.
ここで男を見せて、彼女を助けよう。
I'll show my manliness here and help her.
彼はみんなの前で男を見せた。
He showed off his manliness in front of everyone.