Brain meaning : The control center of the central nervous system of an animal located in the skull which is responsible for perception, cognition, attention, memory, emotion, and action. An intelligent person. (in the plural) Intellect. By analogy with a human brain, the part of a machine or computer that performs calculations. Oral sex. Mind. To dash out the brains of; to kill by smashing the skull. To strike (someone) on the head. To destroy; to put an end to. To conceive in the mind; to understand.