Definition of brain in English:

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Pronunciation: /breɪn/


1An organ of soft nervous tissue contained in the skull of vertebrates, functioning as the coordinating centre of sensation and intellectual and nervous activity: [as modifier]: a brain tumour
More example sentences
  • This occurs as a result of damage to soft brain tissue when the brain rattles against the skull.
  • It is a precious tissue like the nervous tissue of the brain, spinal cord and heart muscle, as it cannot heal like the other tissues.
  • Stem cells are harvested from bone marrow, umbilical cords, the brain and spinal cord and other tissues.
cerebrum, cerebral matter
technical encephalon
1.1 (brains) The substance of an animal’s brain used as food.
Example sentences
  • The Bochka serves pigs roasted on a spit, veal brains with mushrooms in a pot, and grilled salmon.
  • It traditionally contains sweetbreads, brains, porcini mushrooms and chicken livers.
  • Lightly flour the calves' brains and sauté until light brown.
1.2 informal An electronic device with functions comparable to those of the human brain: an electronic brain
More example sentences
  • That shutter speed that the electronic brain says is incorrect, might just give you a wonderful emotive blurry shot that is an award winner!
  • For once, Harry Flashman is happy to let the electronic brain do its thing (but without the flash).
  • If a light shines on it, the brain sends out an electronic pulse.

The human brain consists of three main parts. (i) The forebrain, greatly developed into the cerebrum, consists of two hemispheres joined by a bridge of nerve fibres, and is responsible for the exercise of thought and control of speech. (ii) The midbrain, the upper part of the tapering brainstem, contains cells concerned in eye movements. (iii) The hindbrain, the lower part of the brainstem, contains cells responsible for breathing and for regulating heart action, the flow of digestive juices, and other unconscious actions and processes. The cerebellum, which lies behind the brain stem, plays an important role in the execution of highly skilled movements.

2Intellectual capacity: I didn’t have enough brains for the sciences [mass noun]: success requires brain as well as brawn
More example sentences
  • I think we are also given enough-it goes with the whole thing of what God has given us as far as our brains and our mental capacity goes.
  • Thankfully, the mother had brains enough to send her away again.
  • It is an interesting game that won't exactly tax the brain but feeds the public even more of the voyeuristic TV is so obviously craves!
intelligence, intellect, intellectual capacity, mental capacity, brainpower, cleverness, wit, wits, powers of reasoning, reasoning, wisdom, sagacity, acumen, discernment, shrewdness, judgement, understanding, common sense, sense;
mind, head
informal nous, grey matter, savvy, braininess, upper storey
British informal loaf
North American informal smarts
South African informal kop
2.1 (the brains) informal A clever person who supplies the ideas and plans for a group of people: Tom was the brains of the outfit
More example sentences
  • Could this be the big mo for Ben, Mena and Anil, the brains and the energy behind Typepad and Movable Type?
  • It's time to ask Tommy Champion, the brains and energy behind this event some questions.
  • Ansett liberated them from the old firm and set them up in KordaMentha (putting the brains of the outfit up front there).
clever person, intellectual, intellect, bluestocking, thinker, highbrow, mind, scholar, sage;
genius, Einstein, polymath, prodigy;
informal egghead, bright spark
British informal brainbox, clever clogs, boffin
North American informal brainiac, rocket scientist
2.2A person’s mind: a tiny alarm bell began to ring in her brain
More example sentences
  • I buy expensive creams to put on my skin, even though my science brain knows they don't achieve much.
  • Every once in a while, my brain would clear enough to do some mindless chore, like fill the water pots or fold the blankets, but otherwise, I felt numb.
  • But soon enough your brain starts to run out of gas - opinions, ideas, plans start to float away.


[with object] informal
Hit (someone) hard on the head with an object: she brained me with a rolling pin
More example sentences
  • And in the morning when I looked at him, I asked what he was in for, it seemed that he'd brained his superior officer with a rifle butt.
  • In these streets he met Anitus, the king of the country, and brained him with his club, which was the fashion among gentlemen in those days.
  • Girls that like braining other girls with lacrosse sticks?


have (got) something on the brain

informal Be obsessed with something: John has cars on the brain
More example sentences
  • I have taken to shuffling about on the carpet with my rubber-soled shoes, distributing electric shocks because unlike the boys I don't have balls on the brain and rolling mouse balls along the carpet at a pin just doesn't interest me.
  • I have a patient on the brain as well.
  • Or at least acknowledge that they have it on the brain as much as men do.


Old English brægen, of West Germanic origin; related to Dutch brein.

Words that rhyme with brain

abstain, appertain, arcane, arraign, ascertain, attain, Bahrain, bane, blain, Braine, Cain, Caine, campaign, cane, cinquain, chain, champagne, champaign, Champlain, Charmaine, chicane, chow mein, cocaine, Coleraine, Coltrane, complain, constrain, contain, crane, Dane, deign, demesne, demi-mondaine, detain, disdain, domain, domaine, drain, Duane, Dwane, Elaine, entertain, entrain, explain, fain, fane, feign, gain, Germaine, germane, grain, humane, Hussein, inane, Jain, Jane, Jermaine, Kane, La Fontaine, lain, lane, legerdemain, Lorraine, main, Maine, maintain, mane, mise en scène, Montaigne, moraine, mundane, obtain, ordain, Paine, pane, pertain, plain, plane, Port-of-Spain, profane, rain, Raine, refrain, reign, rein, retain, romaine, sane, Seine, Shane, Sinn Fein, skein, slain, Spain, Spillane, sprain, stain, strain, sustain, swain, terrain, thane, train, twain, Ujjain, Ukraine, underlain, urbane, vain, vane, vein, Verlaine, vicereine, wain, wane, Wayne

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