The Collaborative International Dictionary of English v.0.48:

Girdle \Gir"dle\, n. [OE. gurdel, girdel, AS. gyrdel, fr.
   gyrdan; akin to D. gordel, G. g["u]rtel, Icel. gyr?ill. See
   Gird, v. t., to encircle, and cf. Girth, n.]
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   1. That which girds, encircles, or incloses; a circumference;
      a belt; esp., a belt, sash, or article of dress encircling
      the body usually at the waist; a cestus.
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            Within the girdle of these walls.     --Shak.
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            Their breasts girded with golden girdles. --Rev. xv.
                                                  6.
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   2. The zodiac; also, the equator. [Poetic] --Bacon.
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            From the world's girdle to the frozen pole.
                                                  --Cowper.
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            That gems the starry girdle of the year. --Campbell.
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   3. (Jewelry) The line ofgreatest circumference of a
      brilliant-cut diamond, at which it is grasped by the
      setting. See Illust. of Brilliant. --Knight.
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   4. (Mining) A thin bed or stratum of stone. --Raymond.
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   5. (Zool.) The clitellus of an earthworm.
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   Girdle bone (Anat.), the sphenethmoid. See under
      Sphenethmoid.

   Girdle wheel, a spinning wheel.

   Sea girdle (Zool.), a ctenophore. See Venus's girdle,
      under Venus.

   Shoulder, Pectoral, & Pelvic, girdle. (Anat.) See
      under Pectoral, and Pelvic.

   To have under the girdle, to have bound to one, that is, in
      subjection.
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