This is the 4944th most frequent Japanese word.
祖父
Grandfather.
Used as a familial term referring to one's own grandfather.
私の祖父は昔農業をしていました。
My grandfather used to work in agriculture.
Used to refer to direct interaction with one's own grandfather as part of an activity.
祖父と一緒に公園へ散歩に行きました。
I went for a walk in the park with my grandfather.
Used to refer to someone else's grandfather in an explanatory manner.