parietomastoid suture vs sutura

parietomastoid suture and sutura both are nouns.

Word	Noun	Adjective	Verb	Adverb
parietomastoid suture	Yes	No	No	No
sutura	Yes	No	No	No

As nouns, sutura is a hypernym of parietomastoid suture; that is, sutura is a word with a broader meaning than parietomastoid suture:

parietomastoid suture: the suture between the parietal and the temporal bones
sutura: an immovable joint (especially between the bones of the skull)

Other hypernyms of parietomastoid suture include fibrous joint, suture.

parietomastoid suture (noun)	sutura (noun)
the suture between the parietal and the temporal bones	an immovable joint (especially between the bones of the skull)