If you're tolerant it means that you accept people who are unlike you or put up with stuff you don't like. If you let your roommate play the same awful '80s mix over and over and don't say anything, you're probably a very tolerant person.
Broad-minded and open thinking is a hallmark of tolerant behavior. An individual can be tolerant, and so can a community or a nation if it accepts people from lots of different cultures or backgrounds. We generally think of tolerance as a good thing, but that doesn't mean being tolerant is easy — not with so many family members, classmates, and colleagues around to annoy us.