Concussion

A concussion was an injury to the head.

When Hank fell off his stagecoach, his head was bleeding and he was disorientated. The Sixth Doctor diagnosed him with concussion. (PROSE: Whiskey and Water)

Tegan Jovanka suffered a severe concussion after being knocked down in a scuffle with a Dalek. (TV: Resurrection of the Daleks)

Leo Jones suffered a concussion after being hit by a table during Richard Lazarus' rampage. (TV: The Lazarus Experiment)

The Eleventh Doctor made sure that he and Amy Pond had not sustained a concussion after being ejected from a star whale's mouth. (TV: The Beast Below)

In Paris in 1943, the Thirteenth Doctor used concussion to excuse herself when she asked Noor Inayat Khan where and when she was. (TV: Spyfall)