[W/K] :: Fluid pressure

  Pressure \Pres"sure\ (?; 138), n. [OF., fr. L. pressura, fr.
     premere. See 4th Press.]
     1. The act of pressing, or the condition of being pressed;
        compression; a squeezing; a crushing; as, a pressure of
        the hand.
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     2. A contrasting force or impulse of any kind; as, the
        pressure of poverty; the pressure of taxes; the pressure
        of motives on the mind; the pressure of civilization.
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              Where the pressure of danger was not felt.
                                                    --Macaulay.
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     3. Affliction; distress; grievance.
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              My people's pressures are grievous.   --Eikon
                                                    Basilike.
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              In the midst of his great troubles and pressures.
                                                    --Atterbury.
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     4. Urgency; as, the pressure of business.
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     5. Impression; stamp; character impressed.
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              All saws of books, all forms, all pressures past.
                                                    --Shak.
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     6. (Mech.) The action of a force against some obstacle or
        opposing force; a force in the nature of a thrust,
        distributed over a surface, often estimated with reference
        to the amount upon a unit's area.
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     7. Electro-motive force.
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     Atmospheric pressure, Center of pressure, etc. See under
        Atmospheric, Center, etc.
  
     Back pressure (Steam engine), pressure which resists the
        motion of the piston, as the pressure of exhaust steam
        which does not find free outlet.
  
     Fluid pressure, pressure like that exerted by a fluid. It
        is a thrust which is normal and equally intense in all
        directions around a point. --Rankine.
  
     Pressure gauge, a gauge for indicating fluid pressure; a
        manometer.
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