Okushiri Island (奥尻島 Okushiri-tō?) is an island in Hokkaidō, Japan. It has an area of 142.97 square kilometres (55.20 sq mi). The town of Okushiri and the Hiyama Prefectural Natural Park encompass the entire island. It has many sheep pastures and beech forests. There are several schools, including high, junior high, and elementary. Okushiri currently has no colleges or universities. The name Okushiri comes from the Ainu name I-kus-un-sir (イクㇱウンシㇼ). The phonetic word ikus(un) means other side and sir means island. However, the Japanese meaning of the two kanji used for the name mean "wife's hips" or "wife's buttocks".