thirty-third vs 33rd

thirty-third and 33rd both are adjectives.

Word	Noun	Adjective	Verb	Adverb
thirty-third	No	Yes	No	No
33rd	No	Yes	No	No

As adjectives, thirty-third and 33rd are synonyms defined as:

thirty-third and 33rd: the ordinal number of thirty-three in counting order

thirty-third (adjective)	33rd (adjective)
the ordinal number of thirty-three in counting order	the ordinal number of thirty-three in counting order