Yes, pronounced the same. Apparently the Brits use the Y spelling for earthen dams? After all, they call cigarettes fags so it all gets very confusing. I can imagine some British bloke asking an American girl if you can 'knock her up.' Other definitions: "A wet drainage ditch. The cow got stuck in a dyke." "dyke: a sheet of igneous rock, emplaced in molten state, which cuts across bedding in a sedimentary sequence."

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