(someone) is a big shot

A "big shot" is an important person.

This phrase sometimes has a little bit of a negative tone. You can call someone a "big shot" if they have a high-paying job but don't have time to pay attention to their old friends, for example. Or if you want to tease a friend who's bragging too much, you can say:

All right, Mr. Big Shot!

This phrase appears in these lessons: