One with a nest egg — or pennies, possibly (9)
I believe the answer is:
pensioner
'one with a nest egg' is the definition.
I can't tell whether this definition defines the answer.
'or pennies possibly' is the wordplay.
'possibly' indicates anagramming the letters.
'or'+'pennies'='orpennies'
'orpennies' anagrammed gives 'PENSIONER'.
Can you help me to learn more?
(Other definitions for pensioner that I've seen before include "beneficiary of fund" , "Maybe Chelsea man" , "One past retirement" , "retiree" , "One is older and paid so they don't have to work" .)