vein vs venous

vein is a noun but venous is not a noun.

Word	Noun	Adjective	Verb	Adverb
vein	Yes	No	Yes	No
venous	No	Yes	No	No

vein (noun)	venous (noun)
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

vein (adjective)	venous (adjective)
	of or contained in or performing the function of the veins

vein (verb)	venous (verb)
make a veinlike pattern