from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A violent jarring; a shock. See Synonyms at collision.
- n. An injury to an organ, especially the brain, produced by a violent blow and followed by a temporary or prolonged loss of function.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a violent collision or shock
- n. an injury to part of the body, most especially the brain, caused by a violent blow, followed by loss of function
from the GNU version of the Collaborative International Dictionary of English
- n. A shaking or agitation; a shock; caused by the collision of two bodies.
- n. A condition of lowered functional activity, without visible structural change, produced in an organ by a shock, as by fall or blow.
- n. The unlawful forcing of another by threats of violence to yield up something of value.
from The Century Dictionary and Cyclopedia
- n. The act of shaking or agitating, particularly by the stroke or impact of another body.
- n. The state of being shaken; the shock occasioned by two bodies coming suddenly and violently into collision; shock; agitation.
- n. In surgery, injury sustained by the brain or other viscera, as from a fall, a blow, etc.
- n. In civil law, the act of extorting money or something of value by violence or threats of violence; extortion.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. injury to the brain caused by a blow; usually resulting in loss of consciousness
- n. any violent blow
Middle English concussioun, bruise, contusion, from Latin concussiō, concussiōn-, concussion, from concussus, past participle of concutere, to strike together; see concuss.(American Heritage® Dictionary of the English Language, Fourth Edition)