concussion

(kon-kush’un) [L. concus’sio]. A viclent jar or shock, or a condition which results from it. c. of the brain, a condition caused by violent blows upon the head, attended with vertigo, lo of consciousne , nausea, weak pulse, and slow respiration. c. of the labyrinth, deafne with tinnitus, resulting from a blow oa or explosion near the ear. c. of the retina, impairment of vision from a blow near the eye. c. of the spine, a condition resulting from blows and shocks affecting the cord, attended by muscular weakne and atrophy, pains in limbs and back, anesthesia, and mental and physical deterioration.