Source : Webster's Revised Unabridged Dictionary (1913)

Rotatory \Ro"ta*to*ry\, a. [Cf. F. rotatoire. See {Rotate},
   {Rotary}.]
   1. Turning as on an axis; rotary.

   2. Going in a circle; following in rotation or succession;
      as, rotatory assembles. --Burke.

   3. (Opt.) Producing rotation of the plane of polarization;
      as, the rotatory power of bodies on light. See the Note
      under {polarization}. --Nichol.

Rotatory \Ro"ta*to*ry\, n. (Zo["o]l.)
   A rotifer. [R.] --Kirby.

Source : WordNet®

rotatory
     adj : of or relating to or causing rotation