
Ambatch is a thorny leguminous shrub with yellow flowers growing in the shallows of the Upper Nile and other rivers of tropical Africa. It grows to between four and six metres tall. The wood is very light and spongy and is used to make rafts.
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an Egyptian tree, Aeschynomene elaphroxylon, of the legume family, having a light-colored, spongy wood.
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https://www.infoplease.com/dictionary/ambatch
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