1. A violent jarring; a shock: The concussion from the explosion broke windows three blocks away.
2. An injury to an organ, especially the brain, produced by a violent blow and followed by a temporary or prolonged loss of function.
[Middle English concussioun, bruise, contusion, from Latin concussiō, concussiōn-, concussion, from concussus, past participle of concutere, to strike together; see CONCUSS.]
con·cussive (-kŭsĭv) adj.
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