cyclic vs periodical

cyclic is not a noun while periodical is a noun.

Word	Noun	Adjective	Verb	Adverb
cyclic	No	Yes	No	No
periodical	Yes	Yes	No	No

cyclic (noun)	periodical (noun)
	a publication that appears at fixed intervals

cyclic (adjective)	periodical (adjective)
recurring in cycles	happening or recurring at regular intervals
of a compound having atoms arranged in a ring structure
forming a whorl or having parts arranged in a whorl
conforming to the Carnot cycle
marked by repeated cycles