In almost every family I know, they would be called grandmother. Even though there may not be an actual relationship. In many families, she would be referred to by her first name or as grandfather's wife.
Your great great grandfather.
Your father's grandfather is your great grandfather.
Your great great grandfather.
Your great grandfather
Your great grandfather
Mother in-law
Your father's grandfather is your great grandfather.
Your grandfather's brother is your great uncle.
Sugar Daddy
He would be your great, great grandfather, but you could call him whatever endearing name you and he prefer -- Granddad, Papa, Grandpa, etc.
You call him grandfather.
a grandfather*draw out the vowels an roll the r