brain · noun C /bre…™n/Full view
brain (IN HEAD)
A2 the organ inside your head that controls thought, memory, feelings and activity
Dictionary examples:

Doctors can measure activity in her brain.

The accident left him with permanent brain damage.

His wife died from a brain tumour.

Learner example:

He said the Martians opened his head and [did] experi[ments] with his brain. (Preliminary English Test; B1; Spanish)

brain (INTELLIGENCE)
C1 used to refer to intelligence
Dictionary examples:

That can't possibly be the right way to do it - use your brain!

He's got brains but he's too lazy to use them.

Learner example:

The whole [of] Western society already seems to be founded on computers and relying on chips, which to a certain extent has taken away our own abilities of using our brains. (Certificate in Advanced English; C1; Dutch)

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