concussed

verb

1. (form-of, participle, past)simple past and past participle of concuss

   “The blow concussed him.”

adj

1. Knocked out; temporarily confused or unconscious due to a blow to the head.

   “But, for whatever combination of reasons - and, to be fair, he'd been blasted in the face by shrapnel, was probably badly concussed, and, indeed, would actually remember nothing from the battle after he'd been hit when he was later debriefed - aside from two destroyers left behind to help Hiei, the rest of the Japanese forces withdrew north just before 0300 in the morning.”