Water chestnut [bí qi] water chestnut (English: water chestnut) (scientific name: Eleocharis dulcis), also known as horseshoe, water chestnut, paeoniae, eider gromwell, uyao, Bodhi chestnut, ground pear, is a species of water chestnut in the family Salixaceae. Water chestnut is a shallow watery rooted herb of the Salicaceae family, and is eaten as a vegetable from the bulb. Anciently known as eider grass (eider gromwell), commonly known as horseshoe, also known as ground chestnut, because it is shaped like a horseshoe, but also like chestnuts and so named. Call it horseshoe, only refers to its appearance; said it like chestnut, not only is the shape, even the flavor, composition, function are similar to chestnut, and because it is in the mud results, so there is the chestnut of the name.