資料來源 : Webster's Revised Unabridged Dictionary (1913)

Diaphragm \Di"a*phragm\, n. [L. diaphragma, Gr. ?, fr. ? to
   fence by a partition wall; dia` through + ?, ?, to fence,
   inclose; prob. akin to L. fareire to stuff: cf. F.
   diaphragme. See {Farce}.]
   1. A dividing membrane or thin partition, commonly with an
      opening through it.

   2. (Anat.) The muscular and tendinous partition separating
      the cavity of the chest from that of the abdomen; the
      midriff.

   3. (Zo["o]l.) A calcareous plate which divides the cavity of
      certain shells into two parts.

   4. (Opt.) A plate with an opening, which is generally
      circular, used in instruments to cut off marginal portions
      of a beam of light, as at the focus of a telescope.

   5. (Mach.) A partition in any compartment, for various
      purposes.

   {Diaphragm pump}, one in which a flexible diaphragm takes the
      place of a piston.