I. ˈbrān noun
Etymology: Middle English, from Old English brægen; akin to Middle Low German bregen brain, and perhaps to Greek brechmos front part of the head
Date: before 12th century
1.
a. : the portion of the vertebrate central nervous system enclosed in the skull and continuous with the spinal cord through the foramen magnum that is composed of neurons and supporting and nutritive structures (as glia) and that integrates sensory information from inside and outside the body in controlling autonomic function (as heartbeat and respiration), in coordinating and directing correlated motor responses, and in the process of learning — compare forebrain , hindbrain , midbrain
b. : a nervous center in invertebrates comparable in position and function to the vertebrate brain
2.
a.
(1) : intellect , mind
has a clever brain
(2) : intellectual endowment : intelligence — often used in plural
plenty of brain s in that family
b.
(1) : a very intelligent or intellectual person
(2) : the chief planner of an organization or enterprise — usually used in plural
she's the brain s behind their success
3. : something that performs the functions of a brain ; especially : an automatic device (as a computer) for control or computation
[
brain 1a: 1 cerebral hemisphere, 2 corpus callosum, 3 ventricle, 4 fornix, 5 thalamus, 6 pituitary gland, 7 pons, 8 medulla oblongata, 9 spinal cord, 10 cerebellum, 11 midbrain
]
II. transitive verb
Date: 14th century
1. : to kill by smashing the skull
2. : to hit on the head