in'yōseki 陰陽石

Lit. yin and yang stone. A pair of stones representing male and female principles or genitalia. Also called on'yōseki or on'myōseki, these stones were found in *daimyō teien 大名庭園 where they served as auspicious symbols for fertility, prosperity, and familial harmony. Good examples are found at Kenrokuen 兼六園 in Ishikawa Prefecture and Kōrakuen 後楽園 in Tokyo. In'yōseki may also be called male and female stone, danjoseki 男女石.