ruby vs red

ruby and red both are nouns.

Word	Noun	Adjective	Verb	Adverb
ruby	Yes	Yes	No	No
red	Yes	Yes	No	No

As adjectives, ruby and red are synonyms defined as:

ruby and red: of a color at the end of the color spectrum (next to orange); resembling the color of blood or cherries or tomatoes or rubies

Other synonyms of ruby include blood-red, carmine, cerise, cherry-red, cherry, crimson, reddish, ruby-red, ruddy, scarlet.

As nouns, red is a hypernym of ruby; that is, red is a word with a broader meaning than ruby:

Other hypernyms of ruby include redness.

ruby (noun)	red (noun)
a deep and vivid red color	red color or pigment; the chromatic color resembling the hue of blood
a transparent piece of ruby that has been cut and polished and is valued as a precious gem	emotionally charged terms used to refer to extreme radicals or revolutionaries
a transparent deep red variety of corundum; used as a gemstone and in lasers	the amount by which the cost of a business exceeds its revenue

ruby (adjective)	red (adjective)
of a color at the end of the color spectrum (next to orange); resembling the color of blood or cherries or tomatoes or rubies	(especially of the face) reddened or suffused with or as if with blood from emotion or exertion
	of a color at the end of the color spectrum (next to orange); resembling the color of blood or cherries or tomatoes or rubies
	characterized by violence or bloodshed