Meaning of “grandfather” - Learner’s Dictionary

grandfather

noun [ C ] us uk /ˈɡrændˌfɑːðər/
Extra Examples
His grandfather was a strong influence on him.He's my maternal grandfather.This house once belonged to my grandfather.He was my paternal grandfather.My grandfather finds it difficult to climb stairs now.

A2 the father of your mother or father

(Definition of “grandfather” from the Cambridge Learner’s Dictionary © Cambridge University Press)