Beat one’s brains out

What is Beat one’s brains out?

Beat one’s brains out definition and meaning on Dictionary terms:
Anatomy, Zoology. the part of the central nervous system enclosed in the cranium of humans and other vertebrates, consisting of a soft, convoluted mass of gray and white matter and serving to control and coordinate the mental and physical actions.
Zoology. (in many invertebrates) a part of the nervous system more or less corresponding to the brain of vertebrates.
Sometimes brains. (used with a plural verb) understanding; intellectual power; intelligence.
the brain as the center of thought, understanding, etc.; mind; intellect.

brains, Slang. a member of a group who is regarded as its intellectual leader or planner: The junior partner is the brains of the firm.
Informal. a very intelligent or brilliant person.
Informal. the controlling or guiding mechanism in a computer, robot, pacemaker, etc. the part of a computer system for coordination or guidance, as of a missile.

verb (used with object)
to smash the skull of.
Slang. to hit or bang (someone) on the head.