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noun con·cus·sion \kən-ˈkə-shən\

Simple Definition of concussion

  • : an injury to the brain that is caused by something hitting the head very hard ( US ) ( Brit )

Source: Merriam-Webster's Learner's Dictionary

Full Definition of concussion

  1. 1 a :  a stunning, damaging, or shattering effect from a hard blow; especially :  a jarring injury of the brain resulting in disturbance of cerebral function b :  a hard blow or collision

  2. 2 :  agitation, shaking

concussive play \-ˈkə-siv\ adjective

Examples of concussion in a sentence

  1. She suffered a severe concussion after falling on the ice.

  2. He went to hospital with concussion.

Origin of concussion

Middle English concussioun, from Latin concussion-, concussio, from concutere to shake violently, from com- + quatere to shake

First Known Use: 14th century

Synonym Discussion of concussion

impact, collision, shock, concussion mean a forceful, even violent contact between two or more things. impact may be used to imply contact between two things, at least one of which is impelled toward the other <the glass shattered on impact with the floor>. collision implies the coming together of two or more things with such force that both or all are damaged or their progress is severely impeded <the collision damaged the vehicle>. shock often denotes the effect produced by a collision and carries the suggestion of something that strikes or hits with force <the shock of falling rocks>. concussion when not in technical use, often suggests the shattering, disrupting, or weakening effects of a collision, explosion, or blow <bystanders felt the concussion of the blast>.

Rhymes with concussion

CONCUSSION Defined for Kids


noun con·cus·sion \kən-ˈkə-shən\

Definition of concussion for Students

  1. :  injury to the brain caused by a hard hit on the head

Medical Dictionary


noun con·cus·sion \kən-ˈkəsh-ən\

Medical Definition of concussion

  1. 1:  a hard blow or collision

  2. 2:  a condition resulting from the stunning, damaging, or shattering effects of a hard blow; especially :  a jarring injury of the brain resulting in disturbance of cerebral function and sometimes marked by permanent damage

concussive \-ˈkəs-iv\play adjective

Seen and Heard

What made you want to look up concussion? Please tell us where you read or heard it (including the quote, if possible).


a division or portion of a pool or whole

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