circulatory system vs vein

circulatory system and vein both are nouns.

Word	Noun	Adjective	Verb	Adverb
circulatory system	Yes	No	No	No
vein	Yes	No	Yes	No

circulatory system (noun)	vein (noun)
the organs and tissues involved in circulating blood and lymph through the body	one of the horny ribs that stiffen and support the wing of an insect
	a blood vessel that carries blood from the capillaries toward the heart
	a distinctive style or manner
	a layer of ore between layers of rock
	any of the vascular bundles or ribs that form the branching framework of conducting and supporting tissues in a leaf or other plant organ

circulatory system (verb)	vein (verb)
	make a veinlike pattern