ageing
Scrooge!
Being elderly
Crotchety or cantankerous.
Dotage, declining years, geriatrics, seniority, autumn of life...
Another compound word for grandfather is granddad.
Another word for not old is young.
Another word for getting shots is receiving vaccinations, or being vaccinated.
"Ancient" is another word for very old.
Another word for 40 year old is 4 decades. 8D
Sin.
Another word for an old female cat is a grimalkin.
old
aged
convey
becoming accustomed to
Revenge
Disembarking.