tetrapod vs craniate

tetrapod and craniate both are nouns.

Word	Noun	Adjective	Verb	Adverb
tetrapod	Yes	No	No	No
craniate	Yes	No	No	No

As nouns, craniate is a hypernym of tetrapod; that is, craniate is a word with a broader meaning than tetrapod:

tetrapod: a vertebrate animal having four feet or legs or leglike appendages
craniate: animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium

Other hypernyms of tetrapod include vertebrate.

tetrapod (noun)	craniate (noun)
a vertebrate animal having four feet or legs or leglike appendages	animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium