My French in-laws - three sisters and three brothers all call their mama <Me-mere> or it could be <Mi-mere> and i asked my son. 23 ans, what that meant and he couldn't really relay to me what this term means and how it's used.
He said it was very old fashioned way to refer to your old mother but now is usually used in a deragatory fashion, like in that silly old lady
French speakers kindly enlighten me more about this term. Merci en advance!

mémère is the word. I used to call one of my grand ma that way.
But it can be used in another way, not very nice when you're a bit angry with someone. In car for ex, when the driver yu're following is a bit too slow, you can say "avance mémère!" pépère is the masculine and is used the same way. ça va comme ça Pal?

Oui - maintenant je connais que'est-cq mon fils ca veut dire quand il appele les vieux hommes, de temps en temps comme le cas tu m'a dit avec me-mere en voiture - pepere!
Merci, et avoir un bon week-end!

Passe un bon week end aussi!