A mysterious luminous phenomenon seen at sea (lights appearing on the sea surface at night).
漁師たちは夜に沖合で不知火を見たと話していた。
The fishermen said they saw shiranui (mysterious lights) offshore at night.
不知火は昔からいくつもの民間伝承の題材になっている。
Shiranui has long been the subject of many folk tales.
A variety of citrus fruit called shiranui (also known as dekopon).
スーパーで不知火（デコポン）が旬で甘くて美味しかった。
Dekopon (shiranui) was in season at the supermarket and was sweet and delicious.
この地域は不知火の生産で有名だ。
This region is famous for producing shiranui (dekopon) citrus.