knock out

knock unconscious

Synonyms: coldcock, do in, hamstring, kayo, knock senseless, KO, lay out

Strike or bump (someone or something) out

Render unconscious (as by a blow to the head)

Put to sleep

Complete (especially in haste; knock off)

Cause a mechanism to become non-functional by damaging or destroying it

Communicate (a message) by knocking

to exhaust