Source : WordNet®

man-of-the-earth
     n 1: long-rooted morning glory of western United States [syn: {Ipomoea
          leptophylla}]
     2: tropical American prostrate or climbing herbaceous perennial
        having an enormous starchy root; sometimes held to be
        source of the sweet potato [syn: {wild potato vine}, {wild
        sweet potato vine}, {manroot}, {scammonyroot}, {Ipomoea
        panurata}, {Ipomoea fastigiata}]