freshet
/ˈfreʃɪt/noun
1- the flood of a river from heavy rain or melted snow（大雨或融雪引起的）洪水; 山洪。
1.1
- a rush of fresh water flowing into the sea（入海的）淡水水流。
词源
late 16th cent.: probably from Old French freschete, diminutive of freis 'fresh'.