also: みずめし
noun
rice in cold water; soaked dried rice
Refers to cooked rice that has been washed in cold water, or dried rice that has been soaked in water to soften it. A simple, traditional dish.
夏の暑い日には、冷たい水飯がさっぱりしていて美味しい。
On a hot summer day, cold rice in water is refreshing and delicious.
昔の旅人は、乾飯を水で戻して水飯にして食べた。
Travelers in the old days would rehydrate dried rice with water and eat it as soaked rice.
Compound of 水 (water) and 飯 (cooked rice). The reading すいはん is the on'yomi, while みずめし is a kun'yomi compound. The word simply describes rice prepared with water.