craniate vs tetrapod

craniate and tetrapod both are nouns.

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

As nouns, tetrapod is a hyponym of craniate; that is, tetrapod is a word with a more specific, narrower meaning than craniate:

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

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