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or back pressure

[bak-presh-er] /ˈbækˌprɛʃ ər/
a resistant pressure exerted by liquid or gas against the forward motion or flow of an exhaust or pipe system:
Careful control of backpressure ensures an even supply of oil from the well. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the Web for back pressure
Historical Examples
  • Its use is to show the amount of back pressure, and in a condensing engine to show the degree of vacuum obtained.

  • But the back pressure of the cat's body overloaded the discharge circuits.

    Survival Tactics Al Sevcik
  • The back pressure saved will at once show in the pulling power of the engine, and every one will be surprised.

    Farm Engines and How to Run Them James H. Stephenson
  • There is then no back pressure on the exhaust steam, theoretically.

    Farm Engines and How to Run Them James H. Stephenson
  • So in using steam expansively the back pressure must be at a minimum, and this is especially true in the compound engine.

    Farm Engines and How to Run Them James H. Stephenson
  • He opened the muffler so as to get rid of all back pressure, and opened the throttle to its widest extent.

    Bert Wilson at the Wheel J. W. Duffield
  • The problem now is to get rid of that back pressure, and the old type engines give a hint how it may be done.

    Motors James Slough Zerbe
  • As Bert had already explained to Dick, this was done to eliminate any back pressure from the exhaust gases.

    Bert Wilson at the Wheel J. W. Duffield
  • There is no back pressure of blood here, so that the movement of fluid through the lymphatics is not hindered.

    Physiology Ernest G. Martin
  • The line from d to e is therefore the exhaust line, and that from e to a is the back pressure line or counter pressure line.

British Dictionary definitions for back pressure

back pressure

  1. the pressure that opposes the motion of a piston on its exhaust stroke in an internal-combustion engine
  2. the exhaust pressure in external combustion engines
(med) the local pressure that builds up when fluid flow is obstructed in the cardiovascular or urinary systems
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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back pressure in Medicine

back pressure n.
Pressure exerted upstream in the circulation as a result of obstruction to forward flow, as when congestion in the pulmonary circulation results from failure of the left ventricle.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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