red-orange vs flame-orange

red-orange and flame-orange both are adjectives.

Word	Noun	Adjective	Verb	Adverb
red-orange	No	Yes	No	No
flame-orange	No	Yes	No	No

As adjectives, red-orange and flame-orange are synonyms defined as:

Other synonyms of red-orange include reddish-orange.

red-orange (adjective)	flame-orange (adjective)
of orange tinged with red	of orange tinged with red