じいちゃん Also written 爺ちゃん, 祖父ちゃん Meanings Noun grandfather See also: じいさん. male senior-citizen See also: じいさん. Words containing じいちゃん おじいちゃん子 (おじいちゃんこ) child who is very close to their grandfather おじいちゃんっ子 (おじいちゃんっこ) child who is very close to their grandfather Word lists Familiar language Jinuma: Japanese Dictionary · Word lists