ordinal vs no.

ordinal and no. both are nouns.

Word	Noun	Adjective	Verb	Adverb
ordinal	Yes	Yes	No	No
no.	Yes	No	No	No

As nouns, ordinal and no. are synonyms defined as:

Other synonyms of ordinal include ordinal number.

ordinal (noun)	no. (noun)
the number designating place in an ordered sequence	the number designating place in an ordered sequence

ordinal (adjective)	no. (adjective)
being or denoting a numerical order in a series
of or relating to a taxonomic order