an important influential person;
"he thinks he's a big shot"
"she's a big deal in local politics"
"the Qaeda commander is a very big fish"
- His father is a big wheel in the government.
- Just because Bill is treasurer of our pub's Christmas savings club he thinks he's a financial wizard, but he's only a big fish in a small pond.
- Mr.Black is a big wheel in the auto industry.
- The boss is coming this afternoon to show some big fish around the factory.