treadwheel

from WordNet (r) 3.0 (2006)

treadwheel
    n 1: a mill that is powered by men or animals walking on a
         circular belt or climbing steps [syn: {treadmill},
         {treadwheel}, {tread-wheel}]

from The Collaborative International Dictionary of English v.0.48

Treadwheel \Tread"wheel`\, n.
   A wheel turned by persons or animals, by treading, climbing,
   or pushing with the feet, upon its periphery or face. See
   {Treadmill}.
   [1913 Webster]

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