Methuselah vs old-timer

Methuselah and old-timer both are nouns.

Word	Noun	Adjective	Verb	Adverb
Methuselah	Yes	No	No	No
old-timer	Yes	No	No	No

As nouns, old-timer is a hyponym of Methuselah; that is, old-timer is a word with a more specific, narrower meaning than Methuselah:

Other hyponyms of Methuselah include codger, old codger, antique, gaffer, old geezer, oldtimer, patriarch.

Methuselah (noun)	old-timer (noun)
(Old Testament) a patriarch (grandfather of Noah) who is said to have lived 969 years	an elderly man
a man who is very old	an experienced person who has been through many battles; someone who has given long service