flame up vs flame

flame up is not a noun while flame is a noun.

Word	Noun	Adjective	Verb	Adverb
flame up	No	No	Yes	No
flame	Yes	No	Yes	No

flame up (noun)	flame (noun)
	the process of combustion of inflammable materials producing heat and light and (often) smoke

flame up (verb)	flame (verb)
become ignited	criticize harshly, usually via an electronic medium
burn brightly	be in flames or aflame
	shine with a sudden light