IPA: /ˈpɛnʃənər/
KK: /ˈpɛnʃənər/
A person who receives a regular payment from the government or a private organization after retiring from work.
After many years of service, she became a pensioner and enjoyed her retirement.
Pensioner → It is formed from "pension" (from Old French *pension*, meaning payment or allowance) and "-er" (meaning a person who). A pensioner is a person who receives a pension or payment, typically after retirement.
Think of a 'payment' ('pension') that someone receives regularly, and the '-er' indicates that this person is the one receiving it. A pensioner is someone who gets paid regularly after retiring.