An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

   Homepage   
   


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

<< < -es -it -sc 201 951 abe abs abs aca acc acc aco act ada adh ado aer aft air Alf alg alk alp Alt alt amb ana And ang ani ann ant ant ant apo app app Apu arc arg Arn art ass ast ast ast atm ato att aur aut avo azi bac bal bar bar bat Bea Bel bet bia big bin bio Bir bla bla blo Blu bol Boo bou box bre Bri bro bur cal cal Can cap car Car cat cau cel cen cen cha Cha cha che Chi chr cir cir civ cla clo clo CMB coa coe coh col col col com com com com com com com com Com con con con con con con con con con con con con coo cor cor cor Cos cos cos cou cou cra cri cro cry cul cur cyc D l dar dat day dea dec dec dec def def deg Del Den dep der det deu dew dic dif dif dil dip dir dis dis dis dis dis diu dog Dop dou Dra Dsc dus dwa dyn Dys Ear ecc eco edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ equ eru eth Eur eve exa exc exe exi exo exp ext ext ext fab fai Fan fea fem fer fie fil fir fir fla fli flu foc for for for fra fre fre fri fun fuz gal gal gal Gam gau Gau gen geo geo geo geo Gib glo gov gra gra gra gra gre gro Gui H-a hal Ham har Hay hea hei hel Hel her het hie hig hoa hom hor hot Hub Hug hur hyd hyd hyl hyp ice ide ima ima imp imp inc inc ind ine inf inf inf ing inn ins ins int int int int int int int int inv inv ion iro Isl iso iso Jab jet Jov Jup Kar Kep kil Kip Kra Lag Lam Lan Lar las law lea Leg Leo lev lig lim lin lin lin lit loc loc log Lor low lum lun lun Lym Mac mag mag mag mag mag mai Mal map mas mas mat Mau mea mea med Men mer Mes Met met mic mic Mie mil min Mir mix mod mol mom Moo mor mov mul mur n-b nan nat nea neg Ner neu new New NGC noc nom non non nor nor nuc nuc nul nut obj obl obs occ oct off old one ope opp opt opt orb ord org Ori osc oth ove Owl P-s Pal par par par par Pas pat pec pen per per per per per Pha pha pho pho pho phy pie pix Pla pla pla pla Pli Poi pol pol pol pol por pos pos pow pre pre pre pre pri pri pri pro pro pro pro pro pro pro pub pul pyc qua qua qua qua qui rad rad rad rad rad rad rai ran rar Ray rea Rea rec rec red red ref ref reg rel rel rel ren res res res res ret rev Ric rig rin roc roo rot rot rur S5- Sal sat sca sca Sch sci Scu sec sec sed sel sel sem seq set sha she sho sid sie sil sim sin sit sky slo sno sod sol sol sol sol son sou spa spa spe spe spe spe sph spi spo squ sta sta sta sta ste ste ste Sti sto str str sub sub sub sul sup sup sup sup sur sur syl syn sys tal Tay tel ten ter tex the the the the Tho thr tid tim Tit too Tor tra tra Tra tra Tra tri Tri tru tub tur two Typ ult ult unc uni uni uni upl ura uti val var vec vel ver Ver vie vir vis vis vol W-R war wav wav wea Wei wha wid win WN3 Wol wri xen yok zen zij > >>

Number of Results: 13176 Search : in
tube of flux
  لوله‌ی ِ شار   
lule-ye šâr

Fr.: tube de flux   

Bundles of lines of electrical intensity into which the vector field of electrical force can be divided. Same as tube of force, field tube.

tube; → flux.

Tucana
  توکان   
Tukân (#)

Fr.: Toucan   

The Toucan. A constellation of the southern hemisphere, at approximately 0h right ascension, -65° declination, represented as a toucan, a brightly colored South American bird with a very large, thick bill. Tucana contains the second most prominent → globular cluster in the sky, 47 Tucanae, and the → Small Magellanic Cloud. Abbreviation: Tuc; genitive: Tucanae. The constellation was one of twelve created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman Houtman between 1595 and 1597, and it first appeared in Johann Bayer's Uranometria of 1603.

From Fr., from Portugese tucano, from tucan (onomatopoeia) in the language spoken by the Tupi Indians in Brazil.

Tully-Fisher relation
  بازانش ِ تولی-فیشر   
bâzâneš-e Tully-Fisher

Fr.: relation Tully-Fisher   

An observed correlation between the luminosity of a spiral galaxy and its rate of rotation (measured from its 21 cm hydrogen line). This means that more luminous galaxies have stars that are moving faster. Knowing the rotational velocity of a spiral galaxy, this relation provides its absolute magnitude and then its distance. → Faber-Jackson relation.

Named after R. B. Tully and J. R. Fisher who first derived this relationship (1977, A&A 54, 661); → relation.

tumble
  ۱) کلتاو؛ ۲) کلتاویدن   
1) kaltâv; 2) kaltâvidan

Fr.:   

1) An act of tumbling or falling.
2a) To fall helplessly down, end over end, as by losing one's footing, support, or equilibrium; plunge headlong.
2b) To roll end over end, as in falling (Dictionary.com).

M.E. tum(b)len "to dance in acrobatic style;" perhaps from O.E. tumbian "dance about, tumble, leap;" maybe related to Du. tuimelen, O.H.G. tumon "to reel."

Kaltâv, from Kermâni keletow, Malâyeri kallatow "wobbling," from kal, kalleh "head" + tâv, tow, tâb "swing, twist," from tâbidan "to twist, to spin."

tumbling asteroid
  سیارک ِ کلتاونده، ~ کلتاوگر   
sayyârak-e kaltâvande, ~ kaltâvgar

Fr.:   

An asteroid whose rotational motion does not take place about its → principal axis. Such a behavior can be interpreted as a composition of two or more rotational periods, and described mathematically by a two dimensional → Fourier series (Pravec et al. 2005, Icarus, 173, 108).

The term was first used by A. W. Harris, 1994, Icarus, 107, 209. → tumble; → asteroid.

tumbling motion
  جنبش ِ کلتاوی   
jonbeš-e kaltâvi

Fr.:   

The motion of a solid body whose rotation axis is not fixed in space. For example, that of an asteroid that does not rotate about one of their principal axes. → tumbling asteroid.

tumble; → motion.

tungsten
  تنگستن   
tangestan (#)

Fr.: tungstène   

A very hard, silver-white to steel-gray metal with a body-centered cubic crystalline structure; symbol W. Atomic number 74; atomic weight 183.85; melting point about 3,410°C; boiling point 5,660°C; specific gravity 19.3 at 20°C. The chemical element was discovered by the Swedish chemist Carl-Wilhelm Scheele in 1781. Tungsten metal was first isolated by the Spanish chemists Don Fausto d'Elhuyar and his brother Don Juan Jose d'Elhuyar in 1783.

The name derives from the Swedish ng sten "heavy stone". The chemical symbol, W, is derived from the Ger. wolfram, which was found with tin and interfered with the smelting of tin.

Tunguska event
  رویداد ِ تونگوسکا   
ruydâd-e Tunguska (#)

Fr.: événement de la Toungouska   

The violent impact of a comet or meteorite in the Tunguska region of Siberia on 30 June 1908. The object exploded in the atmosphere before touching the ground at an estimated height of 5-10 km. Observers reported seeing a fireball as bright as the Sun. The explosion caused a shock wave that shook buildings and caused damage, though there was no loss of human life. The first expedition to the remote area of the explosion took place in 1927. An estimated 80 million trees covering more than 2,150 square km were flattened. The energy of the explosion is estimated to have been equivalent to that of about 15 → megatons of TNT , a thousand times more powerful than the atomic bomb dropped on Hiroshima in 1945.

From the name of the central Siberian region, Russ. Podkamennaya (Lower Stony) Tunguska River, today Krasnoyarsk Krai; → event.

tunnel effect
  اُسکر ِ تونل   
oskar-e tunel

Fr.: effet tunnel   

A phenomenon in quantum mechanics whereby a particle can penetrate and cross a potential barrier whose energy is greater than the particle's energy. The tunnel effect, forbidden in classical mechanics, is a direct consequence of the wave nature of material particles. Also called tunneling

M.E. tonel, from M.Fr. tonele, tonnelle "funnel-shaped net," feminine of tonnel,diminutive of tonne "tun, cask for liquids." Sense of "tube, pipe" developed in Eng. and led to sense of "underground passage."

Oskar, → effect; tunel, from Fr. tunnel, as above.

turbid
  تار   
târ (#)

Fr.: turbide   

Having sediment or foreign particles stirred up or suspended; obscured, muddy, such as turbid water.

From L. turbidus "muddy, full of confusion," from turbare "to confuse, disturb," from turba "turmoil, crowd," probably from Gk. tyrbe "turmoil;" cf. Pers. târ "dark, obscure, cloudy," Laki tur "balk, refractory, restive."

Târ "obscure, dark," variant târik "dark;" Mid.Pers. târig "dark," târ "darkness;" Av. taθra- "darkness," taθrya- "dark;" cf. Skt. támisrâ- "darkness, dark night," L. tenebrae "darkness;" Hittite taš(u)uant- "blind;" O.H.G. demar "twilight."

turbidity
  تاری   
târi (#)

Fr.: turbidité   

1) Meteo.: A measure of vertical extinction of solar radiation in the atmosphere. Turbidity is directly related to aerosol concentrations in the tropospheric and stratospheric layers. → visibility.
2) The cloudiness or haziness of a fluid caused by individual particles (suspended solids) that are generally invisible to the naked eye, similar to smoke in air.

turbid; → -ity.

turbine
  توربین   
turbin (#)

Fr.: turbine   

An engine or motor in which the → kinetic energy of a moving → fluid (water, steam, air, or hot gases) acts on the blades, vanes, or buckets of a → rotor to produce rotational motion that can be converted into electrical or mechanical power. In an impulse turbine the turbine is driven by free jets of fluid striking the blades. In a reaction turbine the turbine is driven by the reactive force of a fluid passing through the rotor blades. Turbines are used in hydroelectric power generators, ship propulsion systems, and jet aircraft engines.

From Fr. turbine, from L. turbinem (nominative turbo) "spinning top, eddy, whirlwind," related to turba "turmoil, crowd."

Turbin, loan from Fr., as above.

turbulence
  آشوبناکی   
âšubnâki (#)

Fr.: turbulence   

A state of hydrodynamic → flow in which the velocity at each point fluctuates rapidly and randomly so that only statistical properties can be recognized and subjected to analysis. Turbulence is the most striking manifestation of the non-linear nature of the laws of hydrodynamics, with the irregularity of flows increasing with the → Reynolds number measuring the strength of non-linear effects. The regime of intermediate Reynolds numbers corresponds to a highly non-universal regime of the onset of turbulence, whereas high Reynolds numbers, common in practical situations, characterize the regime of → developed turbulence. → laminar flow; → chaos.

From L. turbulentia, from turbulentus "full of commotion, restless," from turba "turmoil, crowd;" maybe related to Pers. târ "dark, obscure, cloudy," Laki tur "balk, refractory, restive."

šubnâki, from âšub "turmoil, disturbance," âšoftan "to agitate, disturb;" Mid.Pers. âšôb "confusion, turmoil," âšoftan "to destroy, disturb;" Av. xšuf- "to tremble;" cf. Skt. ksobh- "to stagger, begin to swing, tremble;" Pol. chybac "to rock, move to and fro;" Lith. skubus "hasty, fast;" Goth. afskiuban "to shove;" O.E. scufan "to shove;" PIE base *k(w)seubh-, + -nâk state suffix, -i noun suffix.

turbulence decay
  تباهی ِ آشوبناکی   
tabâhi-ye âšubnâki

Fr.: dissipation de turbulence   

The process whereby turbulence evolves by exchanging energy, leading to → dissipation.

turbulence; → decay.

turbulent
  آشوبناک   
âšubnâk (#)

Fr.: turbulent   

The quality of a flow that undergoes → turbulence.

Adj. from → turbulence.

turbulent boundary layer
  لایه‌یِ کرانیِ آشوبناک   
lâye-ye karâni-ye âš:ubnâk

Fr.: couche limite turbulente   

The layer in which the Reynolds stresses are much larger than the viscous stresses. When the → Reynolds number is sufficiently high, there is a turbulent layer adjacent to the → laminar boundary layer.

turbulent; → boundary; → layer.

turbulent core model
  مدل ِ مغزه‌ی ِ آشوبناک   
model-e maqze-ye âšubnâk

Fr.: modèle de cœur turbulent   

A star formation scenario whereby → massive stars form from gravitationally bound → pre-stellar cores, which are supersonically → turbulent and in approximate pressure equilibrium with the surrounding protocluster medium. The high → accretion rates that characterize such media allow accretion to overcome the radiation pressure due to the luminosity of the star. The core is assumed to → collapse via an → accretion disk to form a single star or binary. The core density structure adopted is ρ ∝ r-k, with k = 1.5 set from observations. This choice affects the evolution of the accretion rate, which increases linearly with time. The high densities in regions of massive-star formation lead to typical time scales for the formation of a massive star of about 105 years (McKee & Tan 2003, ApJ 585, 850).

turbulent; → core.

turbulent flow
  تچان ِ آشوبناک   
tacân-e âšybnâk

Fr.: écoulement turbulent   

A → flow characterized by → turbulence. In other words, a flow in which the motion at any point varies unpredictably in direction and magnitude. See also → laminar flow; → transitional flow.

turbulent; → flow.

turbulent Jeans mass
  جرم ِ جینز ِ آشوبناک   
jerm-e Jeans-e âšubnâk

Fr.: masse de Jeans turbulente   

The characteristic mass for → cloud fragmentation in a → turbulent medium. While the standard → Jeans mass depends simply on the gas mean → density and → temperature, and fragmentation is purely gravitational, turbulent Jeans mass depends strongly also on the → Mach number (Chabrier et al. 2014, arXiv:1409.8466).

turbulent; → Jeans; → mass.

turbulent plasma
  پلاسمای ِ آشوبناک   
plasmâ-ye âšubnâk

Fr.: plasma turbulent   

A plasma characterized by a → turbulent flow regime.

turbulent; → plasma.

<< < -es -it -sc 201 951 abe abs abs aca acc acc aco act ada adh ado aer aft air Alf alg alk alp Alt alt amb ana And ang ani ann ant ant ant apo app app Apu arc arg Arn art ass ast ast ast atm ato att aur aut avo azi bac bal bar bar bat Bea Bel bet bia big bin bio Bir bla bla blo Blu bol Boo bou box bre Bri bro bur cal cal Can cap car Car cat cau cel cen cen cha Cha cha che Chi chr cir cir civ cla clo clo CMB coa coe coh col col col com com com com com com com com Com con con con con con con con con con con con con coo cor cor cor Cos cos cos cou cou cra cri cro cry cul cur cyc D l dar dat day dea dec dec dec def def deg Del Den dep der det deu dew dic dif dif dil dip dir dis dis dis dis dis diu dog Dop dou Dra Dsc dus dwa dyn Dys Ear ecc eco edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ equ eru eth Eur eve exa exc exe exi exo exp ext ext ext fab fai Fan fea fem fer fie fil fir fir fla fli flu foc for for for fra fre fre fri fun fuz gal gal gal Gam gau Gau gen geo geo geo geo Gib glo gov gra gra gra gra gre gro Gui H-a hal Ham har Hay hea hei hel Hel her het hie hig hoa hom hor hot Hub Hug hur hyd hyd hyl hyp ice ide ima ima imp imp inc inc ind ine inf inf inf ing inn ins ins int int int int int int int int inv inv ion iro Isl iso iso Jab jet Jov Jup Kar Kep kil Kip Kra Lag Lam Lan Lar las law lea Leg Leo lev lig lim lin lin lin lit loc loc log Lor low lum lun lun Lym Mac mag mag mag mag mag mai Mal map mas mas mat Mau mea mea med Men mer Mes Met met mic mic Mie mil min Mir mix mod mol mom Moo mor mov mul mur n-b nan nat nea neg Ner neu new New NGC noc nom non non nor nor nuc nuc nul nut obj obl obs occ oct off old one ope opp opt opt orb ord org Ori osc oth ove Owl P-s Pal par par par par Pas pat pec pen per per per per per Pha pha pho pho pho phy pie pix Pla pla pla pla Pli Poi pol pol pol pol por pos pos pow pre pre pre pre pri pri pri pro pro pro pro pro pro pro pub pul pyc qua qua qua qua qui rad rad rad rad rad rad rai ran rar Ray rea Rea rec rec red red ref ref reg rel rel rel ren res res res res ret rev Ric rig rin roc roo rot rot rur S5- Sal sat sca sca Sch sci Scu sec sec sed sel sel sem seq set sha she sho sid sie sil sim sin sit sky slo sno sod sol sol sol sol son sou spa spa spe spe spe spe sph spi spo squ sta sta sta sta ste ste ste Sti sto str str sub sub sub sul sup sup sup sup sur sur syl syn sys tal Tay tel ten ter tex the the the the Tho thr tid tim Tit too Tor tra tra Tra tra Tra tri Tri tru tub tur two Typ ult ult unc uni uni uni upl ura uti val var vec vel ver Ver vie vir vis vis vol W-R war wav wav wea Wei wha wid win WN3 Wol wri xen yok zen zij > >>