| accumulator |
an apparatus in a hydraulic or pneumatic system that stores and regulates the supply of fluid that provides pressure in the system. [1/3 definitions] |
| acetylcholine |
a form of this compound used in medicine for its ability to decrease blood pressure and cause muscular movement in such organs as the alimentary canal. [1/2 definitions] |
| acupressure |
a process or technique intended to relieve pain or cure disease by the application of pressure with the hands to specific parts of the body. [1/2 definitions] |
| Addison's disease |
a disease caused by disturbance or failure of the adrenal glands, resulting in anemia, low blood pressure, weakness, and an abnormal brownish tinge to the skin. |
| adiabatic |
of, relating to, or denoting a process that occurs without loss or gain of heat, such as a change in the volume or pressure of the contents of a container. |
| aerosol |
a liquid substance, such as an insecticide, disinfectant, deodorant, or paint, sealed in a container under pressure and dispensed as a fine spray. [1/2 definitions] |
| air bladder |
an air-filled sac in various animals and plants, esp. such a structure located near the spine of certain fish that functions to maintain buoyancy by regulating hydrostatic pressure. (See swim bladder.) |
| air lock |
an airtight compartment in which the air pressure can be regulated, usu. situated between two areas that have different air pressures, as in underwater operations. [1/2 definitions] |
| air mass |
a body of air that covers a wide area and has little horizontal variation in temperature, pressure, or moisture. |
| air pressure |
the pressure of compressed air, as in a tire or pump, or the pressure of the earth's atmosphere. |
| analog computer |
a computer that uses physical quantities such as pressure or electric voltages to represent data. (Cf. digital computer.) |
| aneroid barometer |
a barometer that uses a thin metal disk covering a partial vacuum, such that a change in atmospheric pressure results in a corresponding change in the shape of the disk and moves the indicator needle. |
| anticyclone |
a large system of winds that rotates around a center of high barometric pressure, moving clockwise in the Northern Hemisphere and counterclockwise in the Southern, and usu. producing cool, dry weather. (Cf. cyclone.) |
| arm-twisting |
(informal) the use of unrelenting or unethical pressure in an effort to persuade someone to do something. |
| artesian well |
a well dug through impermeable strata, reaching water that is under pressure. |
| autoclave |
a container made to hold superheated steam under pressure, used for sterilizing medical instruments or the like or for cooking. [1/2 definitions] |
| balloon tire |
a wide tire with deep walls that is inflated with relatively low air pressure to cushion shocks or facilitate travel on sand. |
| bar2 |
a unit of pressure equal to one million dynes per square centimeter. |
| baro- |
weight; pressure. |
| barogram |
a visual record of atmospheric pressure over time, produced by a barograph. |
| barograph |
a barometer that automatically records the atmospheric pressure. |