Cranial nerve and Seventh cranial nerve

Cranial nerve noun - Any of the 12 paired nerves that originate in the brain stem.

Seventh cranial nerve and cranial nerve are semantically related. In some cases you can replace phrase "Seventh cranial nerve" with "Cranial nerve", this phrases are similar.

Seventh cranial nerve noun - Cranial nerve that supplies facial muscles.

Cranial nerve and seventh cranial nerve are semantically related. You can use "Cranial nerve" instead a noun phrase "Seventh cranial nerve".