What do you call your older sister in Japanese?

Important Terms for Sister in Japanese

To refer to your older sister politely, use the term "oneesan", which is pronounced "oh-neigh-sahn". For a more casual way of saying sister, you can opt for "aneki", pronounced "A-ne-key", similar to calling someone "sis." If you're talking about a younger sister, use "imouto", pronounced like "e-moh-oo-toe".