brain Definition in the Cambridge English Dictionary
Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

Definition of “brain” - English Dictionary

Definition of "brain" - American English Dictionary

See all translations

brainnoun [C]

 us   /breɪn/
the ​organ inside the ​head that ​controlsthought, ​memory, ​feelings, and ​physicalactivity: a brain ​tumor brain ​surgery They ​foundfracturedribs, other ​boneinjuries, and brain ​damage. infml A brain is also a very ​intelligentperson: We’ve got the ​best brains in the ​countryworking on this ​problem.
(Definition of brain from the Cambridge Academic Content Dictionary © Cambridge University Press)

Definition of "brain" - British English Dictionary

See all translations

brainnoun

uk   us   /breɪn/
A2 [C] the ​organ inside the ​head that ​controlsthought, ​memory, ​feelings, and ​activity: Doctors ​trieddesperately to ​reduce the ​swelling in her brain. The ​accidentleft him with ​permanent brain damage. His ​wifedied from a brain tumour.C1 [C] used to refer to ​intelligence: Marie has an ​amazing brain (= is very ​intelligent). That can't ​possibly be the ​right way to do it - useyour brain! The ​poorchildinherited his mother's brains and his father's ​looks. He's got brains but he's too ​lazy to use them (= he is ​intelligent but ​lazy). [C usually plural] informal a very ​intelligentperson, ​especially one who has ​spent a lot of ​timestudying: We have the ​best brains in the ​landworking on this ​problem.the brains [S] the most ​intelligentperson in a ​group, ​especially the ​person who ​plans what the ​group will do: My little brother's the brains of the ​family.
More examples

brainverb [T]

uk   us   /breɪn/ informal
to ​hit someone on the ​head: I'll brain you if you don't ​keepquiet.
(Definition of brain from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)

Definition of "brain" - Business English Dictionary

See all translations

brainnoun

uk   us   /breɪn/ informal
[C, usually plural] a very ​intelligentperson: We've got the best brains in the ​industryworking on the ​cars.
the brains [S] the ​personresponsible for the ​planning and ​management of an ​activity or ​organization: the brains behind sth He is the brains behind the corporation's ​success.
(Definition of brain from the Cambridge Business English Dictionary © Cambridge University Press)
What is the pronunciation of brain?
Add Cambridge dictionaries to your browser to your website
Word of the Day

golden

made of gold

Word of the Day

Introducing a new author and a new weekly blog post!
Introducing a new author and a new weekly blog post!
by Cambridge Dictionaries Online,
August 27, 2015
The English language is constantly changing. You know that. But did you know that at Cambridge Dictionaries Online we keep track of the changes? We continually add new words and new meanings to our online dictionary for learners of English. Some of them are new to English entirely (neologisms), and some

Read More 

hyperpalatable adjective
hyperpalatable adjective
August 24, 2015
describes food with heightened levels of sugar and salt, intended to be extremely appealing In Brazil, where the prevalence of overweight and obese adults has doubled since 1980, crisps, biscuits, energy bars and sugary drinks formulated to be ‘hyper-palatable’ are much more widely eaten than previously.

Read More