part of speech: noun

definition 1: the organ inside the skull of humans and animals. The brain is the main part of the central nervous system. It controls the body’s movements and activities and is the center of thought, memory, and feelings.

definition 2: (usually plural) intelligence.

  • It takes a lot of brains to get a good grade on one of Mrs. Kennedy’s tests.

definition 3: (plural) the most intelligent person of a group, or the main planner of something, especially something risky.

  • He was the brains of the group and planned the entire escape.