grizzly vs old

grizzly and old both are nouns.

Word	Noun	Adjective	Verb	Adverb
grizzly	Yes	Yes	No	No
old	Yes	Yes	No	No

grizzly (noun)	old (noun)
powerful brownish-yellow bear of the uplands of western North America	past times

grizzly (adjective)	old (adjective)
showing characteristics of age, especially having grey or white hair	of long duration; not new
	(used especially of persons) having lived for a relatively long time or attained a specific age
	skilled through long experience
	(used for emphasis) very familiar
	excellent
	just preceding something else in time or order
	belonging to some prior time