Male
Man, Guy
A man's gender is known as "male."
だんせい
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
あの男性の名前を知っていますか。
Do you know that guy's name?
このオフィスには男性の会社員が約百名、女性の会社員が約七十名います。
In this office, there are about a hundred male office workers and about seventy female office workers.
この会社で働きたかったら、そこにいる男性に腕相撲で勝利してみせなさい。
If you want to work for this company, beat that guy over there at arm wrestling.