interspersal vs combining

interspersal and combining both are nouns.

Word	Noun	Adjective	Verb	Adverb
interspersal	Yes	No	No	No
combining	Yes	No	No	No

As nouns, combining is a hypernym of interspersal; that is, combining is a word with a broader meaning than interspersal:

interspersal: the act of combining one thing at intervals among other things
combining: the act of combining things to form a new whole

Other hypernyms of interspersal include combination, compounding.

interspersal (noun)	combining (noun)
the act of combining one thing at intervals among other things	the act of combining things to form a new whole
	an occurrence that results in things being united