An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



<< < -wa war wav wav wea wei Whe wid win WNE wor > >>

Number of Results: 210
tâb (#)

Fr.: gauchissement   

The vertical twisting of a → galactic disk in its outer parts. Many → spiral galaxies, including our Milky Way, appear to have warps in the outer reaches of their stellar and gas disks. The rotating body of stars and gas that characterizes a spiral galaxy is generally flat, but the outer regions may deviate from the plane of the disk. The causes are multiple, some warps can come from spontaneous instability, some result from interactions between galaxies, and many reflect the external gas → accretion from intergalactic matter filaments.

M.E. werpen, OE weorpan "to throw;" cf. O.S. werpan, O.N. verpa "to throw," Swed. värpa "to lay eggs," Du. werpen, Ger. werfen "to throw; to distort." Related to warp "threads running lengthwise in a fabric."

Tâb "twisting, bending, waving, a curling lock," variants tâv, tow, tew, from tâbidan, tâftan "to twist, to spin, to bend, to crook," p.p. tâftah "spun, silk or linen cloth," loaned into E. as taffeta (from O.Fr. taffetas, from It. taffeta); similarly Gk. tapetion "little carpet" is probably from this Iranian origin (from which tapestry, tapis); Proto-Ir. *tâp- "to twist, to wind;" cf. L. tempus "time (span);" Lith. tempti "to stretch;" Russ. tepsti "to tighten."

warped disk
  گرده‌ی ِ تابدار، دیسک ِ ~   
gerde-ye tâbdâr, disk-e ~

Fr.: disque gauchi   

A → galactic disk that exhibits a → warp phenomenon.

warp; → disk.



Geology: The slight flexing or bending of the Earth's → crust on a broad or regional scale, either upward or downward.

Verbal noun from → warp (v.).

  زگیل، وروک   
zegil (#), veruk (#)

Fr.: verrue   

Any firm lump growing on the skin, caused by certain viruses and occurring typically on the hands or feet.

M.E., from O.E. wearte, cf. O.N. varta, O.Fris. warte, Du. wrat, O.H.G. warza, Ger. Warze "wart," Russ. vered "ulcer;" L. verus "wart," verruca "swelling, wart; a steep place, height" (Fr. verrue, Sp. verruga, Catalan berruga, It. verruca); Breton guerp "scar, mark;" cognate with the corresponding Pers. words, as below; PIE base *wer- "high raised spot."

Veruk variants varik, vârik, vâruk, bâluk, var, (Gilaki) vadad, and zegil, cognate with L. verruca, from *wer-, as above.
Zegil (prefixed), from *us-wer-, from us- "out," → ex-, + *wer-.

šostan (#)

Fr.: laver   

To apply → water or other → liquid in order to cleanse.

M.E. washen; O.E. wascan, wæscan; cf. O.N. vaska, M.Du. wasscen, Du. wassen, Ger. waschen, from stem *wat-, the root of → water.

Mid.Pers. šustan, šuy- "to wash;" Av. xšaoδah- "flush of water," xšudra- "liquid, fluid; semen;" cf. Skt. ksod- "to dissolve;" Proto-Ir. *xšaud- "to wash" (Cheung 2007).

âxâl (#)

Fr.: déchet   

Unwanted or unusable items, remains, or byproducts. → nuclear waste; → radioactive waste.

M.E., from O.Fr. wast, g(u)ast, from L. vastum, neuter of vastus "waste."

Âxâl "waste, rubbish," of unknown origin.

âb (#)

Fr.: eau   

The normal oxide of hydrogen with formula H2O. Pure water's → melting point is 0°C and its → boiling point 100 °C at sea level. Water has a → maximum density at very nearly 4°C of (by definition) 1.0000 g cm-3. It then expands as its temperature drops to 0°C, the density being 0.9998 g cm-3 . On freezing, it expands still further, giving ice a density of 0.9168 g cm-3 at 0°C, whereas water has a density of 0.9998 g cm-3 at 4 °C. A → water molecule consists of one → oxygen (O) atom bonded to two → hydrogen (H) atoms. The → specific heat of water, 1 calorie per gram per 1 degree C (cal/g/°C), is higher than most other substances. Therefore, water both absorbs and releases heat more slowly than land. This causes land areas to heat more rapidly and to higher temperatures and also cool more rapidly and to lower temperatures, compared to oceans. The high heat capacity of water also explains why the temperatures of land near a body of water are more moderate. The high heat capacity of water keeps its temperature within a relatively narrow range, causing nearby coastal areas to also have a narrow daily and seasonal temperature range. See also → heavy water, → ortho-water, → para-water.

Water, from O.E. wæter (cognates: Du. water; O.H.G. wazzar; Ger. Wasser; Goth. wato); cf. Gk. hydro-, combining form of hydor "water," cognate with Skt. udá- "water;" Khotanese ūtcā "water;" Hittite uātar; L. unda "wave;" O.C.S., Rus. voda; Lith. vanduo; from PIE base *wed- "water; wet."

Âb "water," variants iv, êw, âp; from Mid.Pers. âb "water;" O.Pers. ap- "water;" Av. ap- "water;" cf. Skt. áp- "water;" Hitt. happa- "water;" PIE āp-, ab- "water, river;" cf. Gk. Apidanos, proper noun, a river in Thessalia; L. amnis "stream, river" (from *abnis); O.Ir. ab "river," O.Prus. ape "stream," Lith. upé "stream;" Latv. upe "brook."

water clock
pang (#)

Fr.: clepsydre   

An ancient form of clock, used by several civilizations, consisting of a water container with a small hole from which the water slowly dripped. Time was reckoned by the level of the water remaining in the container.

water; → clock

Pang "a copper bason with a small hole in the bottom, for water in which it is placed to flow through, used for measuring time" used in Iran.

water ice
  یخ ِ آب   
yax-e âb

Fr.: glace d'eau   

Water in the → solid state, produced by freezing → liquid water; frozen water. Ice forms at or below a temperature of 0°C. Ice is less dense than liquid water because it expands during the process of freezing. This is because the molecular arrangement taken by ice leads to an increase in volume and a decrease in density. → maximum density of water

water; → ice.

water maser
  میزر ِ آب   
meyzer-e âb

Fr.: maser H2O   

An interstellar → maser phenomenon in which water (H2O) molecules undergo the processes of → population inversion and → stimulated emission. H2O masers are detected toward star formation regions and the envelopes of evolved stars. The maser emission comes from regions that are typically quite small, not larger than the solar system. The main emission frequency is 22 GHz, which shows up in strong lines. There are, however, other H2O maser transitions at 380 GHz and 183 GHz, which are much weaker than the 22 GHz line. The former transitions are sporadically detected since they are strongly absorbed in the Earth's atmosphere, because of its high water vapor content.

water; → maser

water molecule
  مولکول ِ آب   
molekul-e âb (#)

Fr.: molécule d'eau   

The chemical combination of one → oxygen (O) atom bonded to two → hydrogen (H) atoms. The bonding between the oxygen atom and each hydrogen atom is known as → covalent bonds. The two hydrogen atoms are bonded to the oxygen atom at a 105° angle. This geometry of the water molecule causes it to have positively and negatively changed ends, known as → polarity. Water is referred to a polar or dipolar molecule. The large nucleus of the oxygen atom attracts the shared electrons causing this side of the water molecule to be negatively charged while the hydrogen side is positively charged. This polarity allows water to bond easily with adjacent water molecules.

water; → molecule.

water planet
  سیاره‌ی ِ آبی   
sayyâre-ye âbi

Fr.: planète océan   

Same as → ocean planet.

water; → planet.

water vapor
  بخار ِ آب   
boxâr-e âb (#)

Fr.: vapeur d'eau   

1) Water (H2O) in the gaseous state.
2) Meteo.: Atmospheric water in vapor form; one of the most important components of the → atmosphere.

water; → vapor.

  تنوره‌ی ِ دریایی   
tanure-ye daryâyi (#)

Fr.: trombe marine   

A spinning column of rising humid air that occurs over a body of warm water. Waterspouts fall within the class of atmospheric phenomena known as convective vortices that includes → tornadoes, → dust devils, and → hurricanes. They can feature wind speeds over 200 kilometers per hour.

water + spout, from M.E. spouten akin to M.Du. spiten "to spout;" O.E. spiwan "to spew."

Tanure-ye daryâyi, from tanuré (kešidan) "turning and raising in the air," probably from tanidan "to turn, spin," → tension; daryâyi, → marine.

watt (#)

Fr.: watt   

A unit of power in the SI or MKS system of units, symbol W, equivalent to one joule per second. 1 W = 1 J s-1 = 1 kg m2 s-3 = 1 N m s-1 = 107 erg s-1.
Electricity: The current in amperes multiplied by the electrical potential in volts.

In honor of James Watt (1736-1819) the eminent Scottish inventor and mechanical engineer.

vât-sâ'at (#)

Fr.: watt-heure   

Unit of work or energy, equal to one watt for one hour, or 3.6 x 1010 ergs., or 3600 joules. The kilowatt-hour (kWh), i.e. 1,000 watts over the period of one hour, is the usual unit or measure of electricity supply or consumption. 1 kWh = 3.6 x 106 J.

watt; → hour.

jil (#)

Fr.: barbillon   

A fleshy lobe or appendage hanging down from the throat or chin of certain birds, as the domestic chicken or turkey (

Of uncertain origin.

Jil (in Nâini and Baxtiyâri) "wattle."

vâtsanj (#)

Fr.: wattmètre   

An instrument used for measuring the magnitude of the power in an electric circuit.

watt; → -meter.

mowj (#)

Fr.: onde   

1) General: A raised ridge-shaped formation moving across the surface of a liquid (as of the sea).
2) Physics: A disturbance advancing from point to point in a → medium or → space as in the → propagation of → sound or → light.
See also:
acoustic wave, → acoustic wave equation, → advanced wave, → Alfven wave, → ballistic wave, → blaze wavelength, → bow wave, → collapse of the wave function, → complex wave, → compressional wave, → cosmic microwave background anisotropy, → cosmic microwave background radiation, → decimetric wave, → density wave, → density-wave theory, → elastic wave, → electromagnetic wave, → electrostatic wave, → gravitational wave, → gravity wave, → half-wave plate, → heat wave, → incoherent wave, → Langmuir wave, → longitudinal wave, → Mach wave, → microwave, → microwave background radiation, → microwave radiation, → millimeter wave, → millimeter-wave astronomy, → modulated wave, → Moreton wave, → neutral wave, → P-wave, → periodic wave, → plane wave, → quarter-wave plate, → radio wave, → rarefaction wave, → retarded wave, → Rossby wave, → S-wave, → scalar wave, → seismic wave, → Shack-Hartmann wavefront sensor, → shear wave, → shock wave, → sine wave, → sound wave, → square wave, → standing wave, → stationary wave, → submillimeter wave, → transverse wave, → wave equation, → wave function, → wave mechanics, → wave nature, → wave numbe, → wave optics, → wave packet, → wave plate, → wave theory of light, → wave vector, → wave-particle duality, → waveband, → waveform , → waveform analysis, → wavefront, → wavefront correction, → wavefront distortion, → wavefront sensor, → wavefront tilt, → waveguide, → wavelength, → wavelet, → wavelet theory, → wave train.

M.E. waw; O.E. wagian "to move to and fro," wafian "to wave with the hands" (cf. O.N. vafra "to hover about," M.H.G. waben "to wave, undulate").

Mowj, loan from Ar. mauj.

wave collapse
  رمبش ِ موج   
rombeš-e mowj

Fr.: effondremenr d'onde   

In the → Copenhagen Interpretation of → quantum mechanics, the change undergone by the → wave function of a particle when a measurement is performed on the particle. The wave function collapses to one that has a definite value for the quantity measured. If the → position of the matter wave is measured, it collapses to a localized → pulse. If → momentum is measured, it collapses to a wave with a definite momentum. Same as → collapse of the wave function.

wave; → collapse.

<< < -wa war wav wav wea wei Whe wid win WNE wor > >>