Big cheese is an informal English expression for an important or powerful person. If someone is the big cheese, they are the boss, a leader, or simply the most important person in a group.
The phrase is widely believed to come from chiz, a Hindi or Urdu word meaning thing. In parts of British India, English speakers heard it used in a broader way for something noteworthy, excellent, or significant. Over time, the sound was reshaped in English, and chiz became cheese.
That helps explain why the phrase has nothing to do with dairy. The word cheese in this idiom is probably the result of sound change and borrowing, not a reference to food.
- Meaning today: an important person.
- Likely source: Hindi or Urdu chiz, meaning thing.
- Sense behind it: something notable or excellent came to suggest status.
Example: Everyone waited for the big cheese to approve the plan. The phrase is slightly old fashioned now, but many English speakers still recognize it.