Male, Man, Guy
noun, の adjective
A man's gender is known as "male." Note that this can only refer to a human's gender; you're going to learn the word you use for animals, plants, etc. later on!
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?
それって、男性ホルモンのせいじゃない？
Isn't that because of male hormones?
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.