noun
brain
BRAYN
noun
1
The organ inside the skull that controls thought, memory, emotion, and the rest of the nervous system.
"A concussion is an injury to the brain."
"Scientists are still mapping how different parts of the brain work together."
2
A person's intelligence or mental ability.
"Use your brain and think it through before you answer."
3
An especially intelligent person, or the person supplying the ideas behind a plan.
"She was the brains behind the whole marketing campaign."
verb
1
Informal: to hit someone hard on the head.
"He nearly brained himself on the low doorframe."
How to Use Brain
Learner’s notesIn plain EnglishThe organ that lets you think, or, informally, cleverness/intelligence itself.
Common pairings
use your brain
brain surgery
pick someone's brain
the brains of the operation
Word Forms
brained past tense, brains plural, Brains plural, brains singular
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Etymology
From Old English brægn, going back to a Proto-Germanic root for the same organ.