thirteenth vs ordinal

thirteenth and ordinal both are nouns.

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

thirteenth (noun)	ordinal (noun)
position 13 in a countable series of things	the number designating place in an ordered sequence

thirteenth (adjective)	ordinal (adjective)
coming next after the twelfth in position	being or denoting a numerical order in a series
	of or relating to a taxonomic order