ordinal vs eighth

ordinal and eighth both are nouns.

Word	Noun	Adjective	Verb	Adverb
ordinal	Yes	Yes	No	No
eighth	Yes	Yes	No	No

ordinal (noun)	eighth (noun)
the number designating place in an ordered sequence	one part in eight equal parts
	position eight in a countable series of things

ordinal (adjective)	eighth (adjective)
being or denoting a numerical order in a series	coming next after the seventh and just before the ninth in position
of or relating to a taxonomic order