old-age pension vs pension

old-age pension and pension both are nouns.

Word	Noun	Adjective	Verb	Adverb
old-age pension	Yes	No	No	No
pension	Yes	No	Yes	No

As nouns, pension is a hypernym of old-age pension; that is, pension is a word with a broader meaning than old-age pension:

old-age pension: a monthly payment made to someone who is retired from work
pension: a regular payment to a person that is intended to allow them to subsist without working

old-age pension (noun)	pension (noun)
a monthly payment made to someone who is retired from work	a regular payment to a person that is intended to allow them to subsist without working

old-age pension (verb)	pension (verb)
	grant a pension to