a glancing strike to the chin which causes the jawbone to compress the trigeminal nerve (cranial nerve 5) and cause pain and disorientation
also a single by N.W.A.
Cletus: I know about certain body areas, too. We gotta hit those guys in the ganglia.
Cletus: In the ganglia. That's a mess of nerves under the ear. You gotta drive the jawbone up in that mess of nerves and it rings a bell.
-discussion of chin checking in Rollerball