Different, Separate
noun, の adjective
The kanji and the word are exactly the same. That means they share meanings as well.
べつ
This has the same reading as the kanji you learned, meaning you know the reading!
コウイチが、別の女と歩いているところを見たの。
I saw Koichi walking with a different girl.
それとこれとは話が別だろう。
This and that are two different stories.
その場合は別として、このやり方で男女を別にするのは通常問題ありません。
Aside from that case, it's usually okay to separate the sexes in this way.