My favorite Grandmother was called "Granny".
My kids called their grandmothers, "Grandma and the last name.
My granddaughter calls me "Granny". She calls her other grandmother's and great aunts "Granny and their first name.

Love them all. My daughter has her grand children call he Mare (French for Mother)

Mines Nonnie I like it. It doesn't make me feel old LOL

Grammy

My nick name for Grandma is Baba. My husband got our two and a half year old grandson to use this name for me instead of Grandma. I thought it sounded so old at first but now I kind of like it. It is a European name from where my husband is from.

My odest granson calls me "The Grandmotha"
All the others call me Ma'am. One of the younger grandsons tried to say grandma but his dad say, "That my mom", and the child put the two together and came up with Ma'am and I wouldn't change it for anything. They call my hubby Poppa.

My babies call me Nana.

I'm Mimi to mt grandaughter My friends grandkids call me Nani

When my Granddaughter was born, my Son asked what I wanted to be called. Since I was in college (out of high school 23 yrs before I went back, so early 40's) I decided Grandma was too old sounding. I told him Mama Sheila & they still call me that. :D

When the first grandchild was born, I wasn't yet married to my current husband, her grandfather. My name is Kathy, which she had a difficult time with when she started talking, so she called me Kaky, and what the first grandchild calls you usually sticks, so even though we are now married and he is Paw-paw, I am still Kaky to all the grandkids and I love it, it's unique & they picked it...