forty-second vs 42nd

forty-second and 42nd both are adjectives.

Word	Noun	Adjective	Verb	Adverb
forty-second	No	Yes	No	No
42nd	No	Yes	No	No

As adjectives, forty-second and 42nd are synonyms defined as:

forty-second and 42nd: the ordinal number of forty-two in counting order

forty-second (adjective)	42nd (adjective)
the ordinal number of forty-two in counting order	the ordinal number of forty-two in counting order