Concussion (noun)

1. An injury to the brain caused by a blow or jolt to the head.
2. A temporary loss of consciousness or confusion caused by such an injury.

Origin:

Mid 16th century: from latin concussio(n-), from the verb concutere "shake violently", from con- "together" + quatere "to shake".

Examples:

1. He sustained a concussion in the accident.
2. She sustained a concussion from the fall.
3. The patient was diagnosed with a mild concussion.
4. The athlete was diagnosed with a severe concussion.
5. The soldier was diagnosed with a traumatic concussion.