As nouns the difference between gerontocracy and geriatric
is that gerontocracy is government by elders while geriatric is (slang) an old person.
As an adjective geriatric is
of or pertaining to the elderly.
gerontocracy
English
Noun
(gerontocracies)
Government by elders.
geriatric
English
Adjective
(
en adjective)
Of or pertaining to the elderly.
Of or pertaining to geriatrics.
Noun
(
en noun)
(slang) An old person.