My doctor told me that "trigeminal neuralgia is a severe spastic, lancinating facial pain due to a disorder of the 5th cranial nerve." What does this mean?

It's dictionary time. Clearly you haven't bothered to look up the meanings of the terms used. "Trigeminal" refers to the 5th cranial nerve; "neur + algia" = nerve + pain; lancinating = stabbing. You can figure this out. Look up trigeminal neuralgia. Definitely look at pictures. This is not beyond your comprehension. You're not doing yourself any favors by wanting it spoon-fed to you. Self-education is empowering.
Plain language. Very evere nerve pain that occurs suddenly, in part of the face. Best managed by a neurologist. It can be treated by a neurosurgeon with an operation. If not successfully relieved with medication, see a neurosurgeon.