To shake or stun with a sudden violent force; to cause a concussion in.
From Latin concussus, the past participle of concutere (con- 'together' + quatere 'to shake or strike'). The word entered English in the 17th century, borrowed directly from the Latin past participle rather than evolving naturally.
Medically, concuss led directly to concussion—but the verb itself is rarely used because English speakers prefer 'hit' or 'shake' for the action, yet 'concussion' became the medical term everyone knows, making concuss a verb that was overshadowed by its own noun offspring.
Complete word intelligence in one call. Free tier — 50 lookups/day.