trying on vs fitting

trying on and fitting both are nouns.

Word	Noun	Adjective	Verb	Adverb
trying on	Yes	No	No	No
fitting	Yes	Yes	No	No

As nouns, trying on and fitting are synonyms defined as:

Other synonyms of trying on include try-on.

trying on (noun)	fitting (noun)
putting clothes on to see whether they fit	putting clothes on to see whether they fit
	a small and often standardized accessory to a larger system
	(usually in the plural) furnishings and equipment (especially for a ship or hotel)
	making or becoming suitable; adjusting to circumstances

trying on (adjective)	fitting (adjective)
	being precisely fitting and right
	in harmony with the spirit of particular persons or occasion