What does "diaphragm" mean?

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

Additional senses

  1. 2.(Zoöl.) A calcareous plate which divides the cavity of certain shells into two parts.
  2. 3.(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.
  3. 4.(Mach.) A partition in any compartment, for various purposes. Diaphragm pump, one in which a flexible diaphragm takes the place of a piston.

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