1. The act of pressing, or the condition of being pressed; compression; a squeezing; a crushing; as, a pressure of the hand.

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. "Where the pressure of danger was not felt." (Macaulay)

3. Affliction; distress; grievance. "My people's pressures are grievous." (Eikon Basilike) "In the midst of his great troubles and pressures." (Atterbury)

4. Urgency; as, the pressure of business.

5. Impression; stamp; character impressed. "All saws of books, all forms, all pressures past." (Shak)

6. <mechanics> 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 upon a unit's area. Atmospheric pressure, Center of pressure, etc. See Atmospheric, Center, etc.

<engineering> Back pressure, 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. Pressure gauge, a gauge for indicating fluid pressure; a manometer.

Origin: OF, fr. L. Pressura, fr. Premere.

(01 Mar 1998)