Fr.: pression acoustique
Same as → sound pressure.
To press together; force into less space.
From O.Fr. compresser, from L. compressare "to press together," from comprimere "to squeeze," from → com- "together" + premere "to press;" PIE *prem-/*pres- "to strike."
Tanjidan "to squeeze, press, pull together," related to tang "tight," also "horse girth, a strap for fastening a load" (Mid.Pers. tang "tight, narrow"); cf. Skt. tanákti "draws together, contracts;" cognate with E. → tight; cp. Skt. tanákti "draws together, contracts;" M.H.G. dihte "dense, thick;" Ger. dicht "dense, tight;" O.H.G. gidigan; Ger. gediegen "genuine, solid, worthy;" PIE *tenk- "to thicken, clot; thick, solid."
Pressed into less space; condensed.
Past participle of → compress.
Fr.: air comprimé
Air whose density is increased by being subjected to a pressure greater than atmospheric pressure.
The ability or quality to be reduced in volume. The coefficient of compressibility of a substance is given by c = (1/V).(δV/δp), where δV is the change in the volume resulting from a change of pressure δp, the temperature remaining constant.
Noun from → compressible.
Able to be reduced in volume. → compressible flow.
Adjective from → compress + -ible, variant of -able.
tacân-e tanjidani, ~ tanješpazir
Fr.: flot compressible
A flow in which changes of the density, induced by velocities and their fluctuations, are not negligible.
The act or process of compressing; the state of being compressed.
Verbal noun from → compress.
Fr.: facteur de compression
In thermodynamics, the quantity Z = pVm/RT, in which P is the gas pressure, Vm the molar volume, R the gas constant, and T the temperature. The compression factor is a measure of the deviation of a real gas from an ideal gas. For an ideal gas the compression factor is equal to 1.
Fr.: onde de compression
Fr.: de compression
Of or relating to → compression.
Fr.: onde de compression
An → elastic wave that travels through a → medium with the particles of the medium moving in the same direction as the wave propagation. The compressional wave is the wave that is primarily used in → seismic exploration. Also called P-wave, primary wave, pressure wave.
Fr.: suppression de Compton
Fr.: pression de Coulomb
The repulsive interaction due to the → Coulomb energy between two ions. If the ionic charge is Z, then the Coulomb potential energy is Z2e2/a, where a is some typical separation between the ions. The Coulomb pressure is expected to become important when the ratio ΓC = Z2e2/akT is much larger than 1. In that case, Coulomb effects dominate those of → thermal agitation and the gas settles down into a → crystal.
To cause to undergo → decompression.
1) A gradual decrease in surrounding → pressure,
especially the controlled decrease in pressure that divers undergo
after working in deep water or breathing compressed air.
fešâr-e vâgeni (#)
Fr.: pression de dégénérescence
Pressure in a degenerate electron or neutron gas. → degenerate matter.
1) našib-e ofoq; 2) forubâr; 3)
1) Navigation:→ dip.
Depression, verbal noun of depress, from O.Fr. depresser, from L.L. depressare, frequentative of pressus, p.p. of deprimere "press down," from → de- "down" + premere "to press."
1) Našib-e ofoq, from našib "declivity, descent; lowness of ground, slope of any place" (Mid.Pers. nišēp "declivity, (astrology) dejection," Av. *nixšvaēpā-, xšvaēpā- "bottom, rear") + ofoq→ horizon. 2) Forubâr, from foru "down, downward; below; beneath," → de- + bâr "load, pressure, charge," → charge. 3) Našiblâx, from našib, as above, in item 1, + -lâx place suffix.
Fr.: pression dynamique
A property of a moving → fluid defined by (1/2)ρv2 in → Bernoulli's law, where ρ is → density of fluid and v is → velocity. Dynamic pressure is the difference between → total pressure and → static pressure. Also called → velocity pressure. → ram pressure.
M.E. expressen, O.Fr. espresser "to press, squeeze out; speak one's mind," M.L. expressare, frequentative of exprimere "represent, describe," literally "to press out," from → ex- "out" + pressare "to press, push," from L. premere "to press, hold fast, cover, compress."
Zohâvidan, from zo- variant of os- "out," → ex-, + hâv, from Av. hau- "to press, squeeze out;" cf. Mid.Pers. hunîdan "to express, extract (juice)," hâwan "mortar;" akin to Skt. sav- "to press, press out;" O.H.G. sou, O.E. sēaw "juice;" + -idan infinitive suffix.