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back pressure

noun

Definition of back pressure

1 : residual pressure on the exhaust side of a steam-engine piston against which the steam on the intake side must work
2 : opposition to flow of a liquid or gas due to friction, inertia, gravity, or other cause

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First Known Use of back pressure

1848, in the meaning defined at sense 1

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The first known use of back pressure was in 1848

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