Source : Webster's Revised Unabridged Dictionary (1913)

Waist \Waist\, n. [OE. wast; originally, growth, akin to AS.
   weaxan to grow; cf. AS. w[ae]stm growth. See {Wax} to grow.]
   1. That part of the human body which is immediately below the
      ribs or thorax; the small part of the body between the
      thorax and hips. --Chaucer.

            I am in the waist two yards about.    --Shak.

   2. Hence, the middle part of other bodies; especially
      (Naut.), that part of a vessel's deck, bulwarks, etc.,
      which is between the quarter-deck and the forecastle; the
      middle part of the ship.

   3. A garment, or part of a garment, which covers the body
      from the neck or shoulders to the waist line.

   4. A girdle or belt for the waist. [Obs.] --Shak.

   {Waist anchor}. See {Sheet anchor}, 1, in the Vocabulary.

Source : WordNet®

waist
     n 1: the narrowing of the body between the ribs and hips [syn: {waistline}]
     2: the narrow part of the shoe connecting the heel and the wide
        part of the sole [syn: {shank}]