salmon vs pink-orange

salmon is a noun but pink-orange is not a noun.

Word	Noun	Adjective	Verb	Adverb
salmon	Yes	Yes	No	No
pink-orange	No	Yes	No	No

As adjectives, salmon and pink-orange are synonyms defined as:

Other synonyms of salmon include pinkish-orange.

salmon (noun)	pink-orange (noun)
any of various large food and game fishes of northern waters; usually migrate from salt to fresh water to spawn
a pale pinkish orange color
flesh of any of various marine or freshwater fish of the family Salmonidae

salmon (adjective)	pink-orange (adjective)
of orange tinged with pink	of orange tinged with pink