The word "elder" is similar to "old" or "older." It’s generally used when referring to older people. You can use this word as an adjective or as a noun:
You should respect your elders.
Jeremy’s elder brother moved in with him. (His older brother moved in with him.)
Jimmy Carter is an elder statesmen and former President of the United States.
The village elders came together to decide how to fix the problems in their community.
The word "elderly" is an adjective. Use it as a polite way of saying that a person is old.
Marta is caring for an elderly parent.
That building houses elderly residents.
Bill says that he doesn’t feel elderly even though he has passed the age of 80.
We have an elderly dog that needs a lot of care.
Many elderly people are able to get around with the use of a cane.
