c vs cardinal

c and cardinal both are nouns.

Word	Noun	Adjective	Verb	Adverb
c	Yes	Yes	No	No
cardinal	Yes	Yes	No	No

c (noun)	cardinal (noun)
the 3rd letter of the Roman alphabet	crested thick-billed North American finch having bright red plumage in the male
the speed at which light travels in a vacuum; the constancy and universality of the speed of light is recognized by defining it to be exactly 299,792,458 meters per second	a variable color averaging a vivid red
	(Roman Catholic Church) one of a group of more than 100 prominent bishops in the Sacred College who advise the Pope and elect new Popes
	the number of elements in a mathematical set; denotes a quantity but not the order

c (adjective)	cardinal (adjective)
being ten more than ninety	being or denoting a numerical quantity but not order
	serving as an essential component