My 'grands' call me "Oma". It's the German for Grandmother, But that's not why it was chosen. When my oldest grandchild was born, my son asked me what 'Grandma' name should she use. I told him I'd think about it.
A couple of days later, I gave him my two choices. "G-Ma" or "O-ma", and explained that I was already used to both those names since he and his sisters had been using them for over 20 years.
His response? "Well, gee, Ma! What did you expect us to call you?"
To which I replied, " I rest my case!"
He chose "Oma."
It's my favorite name.