septation vs segmentation

septation and segmentation both are nouns.

Word	Noun	Adjective	Verb	Adverb
septation	Yes	No	No	No
segmentation	Yes	No	No	No

As nouns, segmentation is a hypernym of septation; that is, segmentation is a word with a broader meaning than septation:

septation: the division or partitioning of a cavity into parts by a septum
segmentation: the act of dividing or partitioning; separation by the creation of a boundary that divides or keeps apart

Other hypernyms of septation include division, partition, partitioning, sectionalisation, sectionalization.

septation (noun)	segmentation (noun)
the division or partitioning of a cavity into parts by a septum	the act of dividing or partitioning; separation by the creation of a boundary that divides or keeps apart
	(embryology) the repeated division of a fertilised ovum