carboniferous vs carbon

carboniferous is not a noun while carbon is a noun.

Word	Noun	Adjective	Verb	Adverb
carboniferous	No	Yes	No	No
carbon	Yes	No	No	No

carboniferous (noun)	carbon (noun)
	a copy made with carbon paper
	an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds
	a thin paper coated on one side with a dark waxy substance (often containing carbon); used to transfer characters from the original to an under sheet of paper

carboniferous (adjective)	carbon (adjective)
relating to or consisting of or yielding carbon
of or relating to the Carboniferous geologic era