1. the organ inside the head that controls thought, memory, feelings, and bodily functions
Usage: plural form of brain
2. intelligence or mental ability
Usage: informal
3. the most intelligent person in a group
Usage: informal

Examples

• The human brain weighs about three pounds.
• She has the brains to solve this problem.
• He’s the brains of the operation.
• The accident damaged parts of his brain.
• You need brains, not just luck, to succeed.
• She’s got more brains than the rest of us combined.
• The brains behind the company’s success retired last year.