I. ˈbrān noun
( -s )
Etymology: Middle English, from Old English brægen; akin to Old Frisian brein brain, Middle Low German bregen brain, Greek brechmos front part of the head
1.
a. : the portion of the vertebrate central nervous system that constitutes the organ of thought and neural coordination, including all the higher nervous centers, receiving impulses from the sense organs, and interpreting and correlating these with stored impressions to formulate the motor impulses that ultimately control all vital activities, that is made up of neurons and their processes organized into layers and nuclei of gray matter and tracts, decussations, and fasciculi of white matter together with various supporting and nutritive structures, and that is enclosed within the skull, being continuous with the spinal cord through the foramen magnum and with the cranial nerves through various other openings — see forebrain , hindbrain , midbrain ; compare cortex , ventricle
b. : a nervous center in invertebrates (as the supraesophageal ganglia of arthropods) corresponding in position and function more or less to the brain of vertebrate animals — compare cerebral ganglion
2.
a.
(1) : intellect , mind
it took a queer brain to think up such a scheme
successful in reading a man's brain — Lou Richter
(2) : sheer intellect — often used in plural
he's got brains but no common sense
(3) : intellectual endowment : intelligence — often used in plural
there's plenty of brains in that family
b.
(1) : a supremely bright or intelligent person
he'd been known as a brain throughout college
(2) : the guiding genius or intellectual leader : supreme planner — usually used in plural
the brains of the Nazi party
he was the brains of the enterprise
Synonyms: see mind
•
- on the brain
[s]brain.jpg[/s] [
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. adjective
Etymology: Middle English, from brain (I)
archaic Scotland : mad , furious
III. transitive verb
( -ed/-ing/-s )
Etymology: Middle English brainen, from brain (I)
1. : to kill by smashing in the skull
a small flail loaded with lead to brain the … assassins — T.B.Macaulay
2. : to bang on the head
brain a person with a book
IV. noun
: something that performs the functions of a brain ; especially : an automatic device (as a computer) used for control, guidance, or computation
the brain of a missile