Grandmother

外婆

wàipó

(mother of someone's parent)

外祖母

wàizǔmǔ

(mother of someone's parent)

奶奶

nǎinai

(mother of someone's parent)

姥姥

lǎolao

(mother of someone's parent)

祖母

zǔmǔ

(mother of someone's parent)