old (having lived or existed for a long time): He is now an old man. My old car consumes much gasoline.
aged (very old): He had to look after his aged father.
elderly (a polite word for old): Elderly are eligible for financial assistance.
no spring chicken (not young): I’m not a spring chicken, I’m fifty years old.
in one’s dotage (old and weak): I have to look after my grandmother, she’s in her dotage.
