Language: Old English
Origin: brægen


1 noun
Related topics: Biology, Human
brain1 S2 W2


[countable]HBHHB the organ inside your head that controls how you think, feel, and move:
Messages from the brain are carried by the central nervous system.
the chemistry of the brain
the human brain
the right/left hemisphere of the brain (=the right or left side of the brain)
Emotional responses are a function of the right hemisphere of the brain.
She died of a brain tumour.


[countable usually plural, uncountable] the ability to think clearly and learn quickly:
If you had any brains, you'd know what I meant.
The job requires brains.
Something's addled your brains (=made you confused).
Come on, use your brain, John.


[countable usually plural] informal someone who is intelligent, with good ideas and useful skills:
Some of our best brains are leaving the country to work in the US.
brain drain


[uncountable] also brains [plural] the brain of an animal, used as food

have something on the brain

informal to be always thinking about something:
I've got that song on the brain today.

be the brains behind/of something

to be the person who thought of and developed a particular plan, system, or organization, especially a successful one:
Danny's definitely the brains of the project.

brain dead

a) MI in a state where your brain has stopped working properly even though your heart may still be beating
b) informal in a state in which you seem stupid or uninteresting, especially because you live a boring life or are very tired

brain box

British English informal a very intelligent person
bird-brain, hare-brained

; ➔ beat your brains out

at beat1 (22)

; ➔ pick somebody's brains

at pick1 (7)

; ➔ rack your brain(s)

at rack2 (2)

Dictionary results for "brain"
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