Your mother's uncle is your great uncle and you are his great niece (if you are a girl) or great nephew (if you are a boy). He probably calls you by your personal name, Joe or Jane, etc.
Your Uncle.
I call my mother mom
Your mother's mother is your grandmother.
He is your uncle, in most families he would be Uncle (Jack, Fred or what ever his first name is).
His relationship to you is brother-in-law.
Your mothers brother is you maternal uncle.
uncle
well my moms uncle is my uncle too. so it would be the daughters uncle also.
your uncle
That would be an uncle.
uncle
Name your mom's uncle's son with something that means something to you or your family.