Con*cus"sion (?), n. [L. concussio, fr. concutere, concussum, to shake violenty; con- + quatere to shake. See Cashier, Quash.] 1. A shaking or agitation; a shock; caused by the collision of two bodies.

It is believed that great ringing of bells, in populous cities, hath dissipated pestilent air; which may be from the concussion of the air.
Bacon.

2. (Med.) A condition of lowered functional activity, without visible structural change, produced in an organ by a shock, as by fall or blow; as, a concussion of the brain.

3. (Civil Law) The unlawful forcing of another by threats of violence to yield up something of value.

Then concussion, rapine, pilleries,
Their catalogue of accusations fill.
Daniel.

Concussion fuse(Mil.), one that is ignited by the concussion of the shell when it strikes.

Syn. -- See Shock.