n. [ L. acus needle + premere, pressum, to press. ] (Surg.) A mode of arresting hemorrhage resulting from wounds or surgical operations, by passing under the divided vessel a needle, the ends of which are left exposed externally on the cutaneous surface. Simpson. [ 1913 Webster ]

n. Compression. [ 1913 Webster ]

n. The act of expressing; expression; utterance; representation. [ Obs. ] [ 1913 Webster ]

An operation more divine
Than breath or pen can give expressure to. Shak. [ 1913 Webster ]

a. 1. Having or involving a pressure greatly exceeding that of the atmosphere; -- said of steam, air, water, etc., and of steam, air, or hydraulic engines, water wheels, etc. [ 1913 Webster ]

2. Fig.: Urgent; intense; as, a high-pressure business or social life. [ 1913 Webster ]

3. Using intense psychological pressure or other incentives to convince others to do things; aggressively persistent; as, high-pressure salesmen; high-pressure tactics. [ PJC ]

High-pressure engine, an engine in which steam at high pressure is used. It may be either a condensing or a noncondensing engine. Formerly the term was used only of the latter. See Steam engine. [ 1913 Webster ]

n. [ Cf. OF. impressure, LL. impressura. ] Dent; impression. [ Obs. ] Shak. [ 1913 Webster ]

a. 1. Having, employing, or exerting, a low degree of pressure. [ 1913 Webster ]

2. same as easygoing, 4; as, a low-pressure salesman.
Syn. -- easygoing. [ WordNet 1.5 ]

Low-pressure steam engine, a steam engine in which low steam is used; often applied to a condensing engine even when steam at high pressure is used. See Steam engine. [ 1913 Webster ]

n. Oppression. [ Obs. ] [ 1913 Webster ]

n. (Physical Chemistry) The pressure which a solution of a substance in a liquid exerts on a semipermeable membrane, through which the solvent can diffuse but the dissolved substance (the solute) cannot diffuse, when separated across the membrane from the pure solvent. In general, the osmotic pressure will depend almost proportionally up to certain concentrations upon the molal concentration of the solute. [ PJC ]

n. Excessive pressure or urging. London Athenaeum. [ 1913 Webster ]

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. [ 1913 Webster ]

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. [ 1913 Webster ]

Where the pressure of danger was not felt. Macaulay. [ 1913 Webster ]

3. Affliction; distress; grievance. [ 1913 Webster ]

My people's pressures are grievous. Eikon Basilike. [ 1913 Webster ]

In the midst of his great troubles and pressures. Atterbury. [ 1913 Webster ]

4. Urgency; as, the pressure of business. [ 1913 Webster ]

5. Impression; stamp; character impressed. [ 1913 Webster ]

All saws of books, all forms, all pressures past. Shak. [ 1913 Webster ]

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. [ 1913 Webster ]

7. Electro-motive force. [ Webster 1913 Suppl. ]

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. [ 1913 Webster ]

. 1. (Cookery) a pot with a lid which may be tightly bound to the bottom part, forming a vessel which can withstand some gas pressure from within. It is used to heat foods in water or steam to a temperature somewhat above the boiling point of water, allowing the cooking process to be accomplished more quickly than otherwise. [ PJC ]

2. Fig., a situation involving intense psychological pressure due to multiple urgent demands, as in certain job situations. [ PJC ]

. (Elec.) Wires leading from various points of an electric system to a central station, where a voltmeter indicates the potential of the system at those points. [ Webster 1913 Suppl. ]

{ or }. (Physics) The pressure or tension of a confined body of vapor of a chemical substance in equilibrium with the solid or liquid form of the substance. The pressure of a given saturated vapor is a function of the temperature only, and may be measured by introducing a small quantity of the substance into a barometer and noting the depression of the column of mercury. [ Webster 1913 Suppl. +PJC ]