extinct vs extinction

extinct is not a noun while extinction is a noun.

Word	Noun	Adjective	Verb	Adverb
extinct	No	Yes	No	No
extinction	Yes	No	No	No

extinct (noun)	extinction (noun)
	the act of extinguishing; causing to stop burning
	a conditioning process in which the reinforcer is removed and a conditioned response becomes independent of the conditioned stimulus
	complete annihilation
	the reduction of the intensity of radiation as a consequence of absorption and radiation
	no longer in existence
	no longer active; extinguished

extinct (adjective)	extinction (adjective)
no longer in existence; lost or especially having died out leaving no living representatives
(of e.g. volcanoes) permanently inactive
being out or having grown cold