Source : Webster's Revised Unabridged Dictionary (1913)
Water wheel \Wa"ter wheel`\
1. Any wheel for propelling machinery or for other purposes,
that is made to rotate by the direct action of water; --
called an {overshot wheel} when the water is applied at
the top, an {undershot wheel} when at the bottom, a
{breast wheel} when at an intermediate point; other forms
are called {reaction wheel}, {vortex wheel}, {turbine
wheel}, etc.
2. The paddle wheel of a steam vessel.
3. A wheel for raising water; a noria, or the like.
Turbine \Tur"bine\, n. [L. turbo, -inis, that which spins or
whirls round, whirl.]
A water wheel, commonly horizontal, variously constructed,
but usually having a series of curved floats or buckets,
against which the water acts by its impulse or reaction in
flowing either outward from a central chamber, inward from an
external casing, or from above downward, etc.; -- also called
{turbine wheel}.
Note: In some turbines, the water is supplied to the wheel
from below, instead of above. Turbines in which the
water flows in a direction parallel to the axis are
called parallel-flow turbines.