When one of their grandparents is non-Japanese, クオーター kuōtā (= quarter) is used, but there is no specific word for three or more mixed ethnicity. It will be explained as, for instance, 父親がフランスとドイツのハーフで、母親が日本人 Chihioya ga Furansu to Doitsu no hāfu de, hahaoya ga nihonjin (My father is half French and half German, and my mother is Japanese) or like that.