prosperous vs halcyon

prosperous is not a noun while halcyon is a noun.

Word	Noun	Adjective	Verb	Adverb
prosperous	No	Yes	No	No
halcyon	Yes	Yes	No	No

As adjectives, prosperous and halcyon are synonyms defined as:

Other synonyms of prosperous include golden.

prosperous (noun)	halcyon (noun)
	a mythical bird said to breed at the time of the winter solstice in a nest floating on the sea and to have the power of calming the winds and waves

prosperous (adjective)	halcyon (adjective)
marked by peace and prosperity	marked by peace and prosperity
presaging or likely to bring good luck or a good outcome	idyllically calm and peaceful; suggesting happy tranquillity
in fortunate circumstances financially; moderately rich
very lively and profitable