frontal suture vs sutura

frontal suture and sutura both are nouns.

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

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

frontal suture: the suture between two halves of the frontal bone (usually obliterated by the age of 6)
sutura: an immovable joint (especially between the bones of the skull)

Other hypernyms of frontal suture include fibrous joint, suture.

frontal suture (noun)	sutura (noun)
the suture between two halves of the frontal bone (usually obliterated by the age of 6)	an immovable joint (especially between the bones of the skull)