Source : Webster's Revised Unabridged Dictionary (1913)

Flotation \Flo*ta"tion\, n. [Cf. F. flottation a floating,
   flottaison water line, fr. flotter to float. See {Flotilla}.]
   1. The act, process, or state of floating.

   2. The science of floating bodies.

   {Center of flotation}. (Shipbuilding)
      (a) The center of any given plane of flotation.
      (b) More commonly, the middle of the length of the load
          water line. --Rankine.

   {Plane, or Line}, {of flotation}, the plane or line in which
      the horizontal surface of a fluid cuts a body floating in
      it. See {Bearing}, n., 9
      (c) .

   {Surface of flotation} (Shipbuilding), the imaginary surface
      which all the planes of flotation touch when a vessel
      rolls or pitches; the envelope of all such planes.

Source : WordNet®

center of flotation
     n : the center of gravity of a floating object [syn: {centre of
         flotation}]