Buddhist Monk
noun
さん is what you put on people's names. It's sort of like "Mr." So a "Mr. Monk" is a monk — specifically a Buddhist monk.
坊さん is a casual term for monks. Even in its more polite form, お坊さん, it's still a bit too informal to use when speaking directly to a monk. So it's okay to use when you're talking about them, but not to them!
The reading is the one you learned with the kanji. ぼうさん！
あの坊さんには、アメリカ人の血も混じっているんですよ。
That monk has American blood in him.
人は見かけだけでは判断できないよ。例えば、アイツはヤクザみたいな見た目をしているけど、実は坊さんなんだぜ。
Appearances can be deceptive. For example, he looks like a yakuza, but he is actually a monk.
くそ、彼女が付き合ってる坊さんたちには太刀打ちできねーよ。あいつら俺とはかなりレベルが違うんだ。
Man, I can’t compete with the monks she goes out with. They’re on a whole other level.