older-elder

[nado92]

what is the difference between older and elder?

[sarat_106]

what is the difference between older and elder?

Both are comparative form of the adjective ‘old’. You can say:
Old….. older …..oldest
or
old ……elder……. eldest.
Both imply having greater age than something or someone else. While ‘older’ finds common use, Elder, has restricted application and is used chiefly to indicate seniority in age as between any two people but especially priority of birth as between children born of the same parents:
The elder brother became a minister.
He is an elder statesman enjoying considerable respect.
There is tax incentives for elder citizen in India.

You can also use elderly as a polite or respectable word for the ‘old’ people.
He visits his elderly parents very often.

[Tdol]

You can say older than but not elder than.

Also, while the elderly is a polite term, in the UK older people is being used more and more.