top dog
Plural
top dogs
1
a person who holds the highest rank in a particular group or organization
The idiom "top dog" comes from the world of dog fighting, where the top dog was the most successful or dominant fighter. It is typically used to describe a person or organization that is dominant or successful in their field.
- By the time they realized they weren't the top dog anymore, it was too late to catch up.
- He's the top dog in the company and has a lot of influence over its direction.
- They have been trying to become the top dog in their field for years, and are finally starting to make progress.
- They were the top dog in the industry for years, but lost their position after a series of scandals.