platyrhinian vs platyrrhinian

platyrhinian is not a noun while platyrrhinian is a noun.

Word	Noun	Adjective	Verb	Adverb
platyrhinian	No	Yes	No	No
platyrrhinian	Yes	Yes	No	No

As adjectives, platyrhinian and platyrrhinian are synonyms defined as:

platyrhinian and platyrrhinian: of or related to New World monkeys having nostrils far apart or to people with broad noses

Other synonyms of platyrhinian include broadnosed, platyrhine, platyrrhine, platyrrhinic.

platyrhinian (noun)	platyrrhinian (noun)
	hairy-faced arboreal monkeys having widely separated nostrils and long usually prehensile tails

platyrhinian (adjective)	platyrrhinian (adjective)
of or related to New World monkeys having nostrils far apart or to people with broad noses	of or related to New World monkeys having nostrils far apart or to people with broad noses