iridescent vs nacreous

iridescent and nacreous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
iridescent	No	Yes	No	No
nacreous	No	Yes	No	No

As adjectives, iridescent and nacreous are synonyms defined as:

Other synonyms of iridescent include opalescent, opaline, pearlescent.

iridescent (adjective)	nacreous (adjective)
having a play of lustrous rainbow colors	consisting of or resembling mother-of-pearl
varying in color when seen in different lights or from different angles	having a play of lustrous rainbow colors