Worn or smoothed by the action of water.(adjective)
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Use "waterworn" in a sentence
"Through the bowels of the Great Alpine Reef, they spun, slipping along the smooth, waterworn sides."
"Other portions of woods had their ends waterworn, and were full of long cracks, such as appear in wood long exposed to the sun."
"On these rounded off banks or bergs of forest land, Youranigh drew my attention to large, old, waterworn, trunks of trees, which he showed me had been deposited there by floods."