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

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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<< < -es -iv -ti 21- A r abe abs abs acc acc acc act act ada adi adu aff age alc Alf ali all alp alt ama amp ana ang ang ann ano ant ant ape apo app aps arc Arg ari art ass ast ast ast atm ato att aur aut axi B r bac Bal Bar Bar Bay bec Ber Bet Bie bij bin bio bis bla bla blu blu bol Bor bou Bra bre bro Bug C-s cal Cam can car Car Cas cat cav cel cen cer Cha cha cha che cho cir cir cir cla clo clo clu 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 coo cor cor cor cos cos cos Cou cou Cra Cre cri cro cub cur cyc cyl dar dat daw de- Deb dec dec dee def deg del Den dep der det deu dew dic dif dif dil dip dir dis dis dis dis dis div dog Dop dou dra dua dus dwa dyn e-m ear ecl eco eff ein Ein elb ele ele ele ele Els emi emp ene enr env epi equ equ Eri est Euc eva evo exc exc exh exo exp exp ext ext f-n Fah fam fau fee Fer fib fil fin fir fix fle flu foc for for for fra fre fre fri fun fuz gal gal gal Gan gau GCN gen geo geo geo geo Gl glo gra gra gra gra gra gre gro GW1 hab hal han HAR haz hea hel hel Hen Her heu Hig Hil hol hop hor hou Hub Hum Hyd hyd hyd hyp hys ide ign ima imp imp inc inc ind ine inf inf inf inh INP ins ins int int int int Int int int int inv ion iri irr iso iso iso Jea Jos Jun K2 Kep key kin Kol lag lam Lan lar las lav lea leg len lev lig lim lin lin lin lis lob loc log lor low lum lun lun Lym Mac mag mag mag mag mag mai Mal mar mas mas mat max mea mea mee Men mer met met met mic mid Mil min Mir mix mod mod mol mon Mor mou mul muo mys nan nat nav nec Nep neu New New NGC nob nom non non nor not nuc nuc num Nyq obj obs obs oce oen OH omn opa ope opt opt opt orb ord Ori ort osc out ove oxy pal pan par Par par par pas pea Pen per per per per per pet pha pho pho pho phy pie Pit Pla pla pla pla ple Poi pol pol pol pol pop pos pos pow pre pre pre Pre pri pri pri pro pro pro pro pro pro Pro pub pul pyr qua qua qua qua Qui rad rad rad rad rad rad ram ran rat rea rec rec rec red ref ref reg reg rel rel rem rep res res res ret rev rho Rie rim riv rol Ros rot rul S a Sah san Sat sca Sch Sch scr sec sec sec sei sel sem sep set sha she sho sid sig sil sim sin sit sky slu sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spl spr sta sta sta sta sta ste ste sti sto str str sub sub sub sug sun sup sup sup sup sur syl syn sys tal Tay tel ten ter tex the the the thi tho thu tid tim tod top tot tra tra tra tra tri tri tro tru tur twi Typ UFO ult unc uni uni uni upg ura uti val var vec vel ver ver vig vir vis voc von wak Was wav wax wea wei whi Wie win WN6 wom X-r yel you zer zod > >>

Number of Results: 12948 Search : far
stilb (sb)
  استیلب   
estilb

Fr.: stilb   

Optics: A unit of luminance equal to one candle per square cm.

From Gk. stilbe "lamp."

stimulate
  گوازیدن   
gavâzidan

Fr.: stimuler   

To cause physical activity in something; e.g. → stimulated emission.

Verb from → stimulus.

stimulated emission
  گسیل ِ گوازیده   
gosil-e gavâzidé

Fr.: émission stimulée   

The process by which an electron, which is already in an excited state (an upper energy level, in contrast to its lowest possible level or "ground state"), can "stimulate" a transition to a lower level, producing a second photon of the same energy. The quantum energy of the incoming photon should be equal to the energy difference between its present level and the lower level. This process forms the basis of both the → laser and → maser. Same as → induced emission.

Stimulated, p.p. of → stimulate; → emission.

stimulated star formation
  دیسش ِ گوالیده‌ی ِ ستاره   
diseš-e gavâlide-ye setâré

Fr.: formation stimulée d'étoiles   

A process in which a star is not formed spontaneously but is provoked by the action of external forces, such as pressure and shock on a molecular cloud by close-by → massive stars, → supernova explosions, etc. See also → sequential star formation.

Stimulated, p.p. of → stimulate; → star formation.

stimulus
  گواز   
gavâz

Fr.: stimulus   

Something that incites or rouses to action; an incentive.
Physiology: Something that causes a physical response in an organism,

From L. stimulus "goad, spur;" cognate with Pers. tizsharp.

Gavâz "goad, a stick with a pointed end, for driving cattle," Mid.Pers. *gawâz, lowned in Arm. gawazan "goad;" Av. gauuāza- "whip, stick for driving cattle," from gao- "cattle, cow" (→ Bootes) + āza-, from az- "to drive," azaiti "drives;" cf. Skt. aj- "to drive," ájati "drives;" Gk. agein "to lead, guide, drive;" L. agere "to do, set in motion," → act.

Stirling's approximation
  نزدینش ِ استرلینگ   
nazdineš-e Stirling

Fr.: approximation de Stirling   

A mathematical formula yielding an approximate value for → factorial n, when n is large: n! ≅ (2πn)1/2nne-n, where e is the base of → natural logarithm.

Named after James Stirling (1692-1770), a Scottish mathematician; → approximation.

stochastic
  کاتورگین   
kâturgin

Fr.: stochastique   

Involving or containing a random variable or variables. A stochastic variable is neither completely determined nor completely random. A system containing one or more stochastic variables is probabilistically determined.

From Gk. stokhastikos "able to guess, conjecturing," from stokhazesthai "to aim at, guess," from stokhos "a guess, target," literally "pointed stake."

Kâturgin, from kâtur, kâturé, → random + -gin, adj. suffix, contraction of âgin "filled."

stochastic excitation
  بر‌انگیزش ِ کاتورگین   
barangizeš-e kâturgin

Fr.: excitation stochastique   

The mechanism arising from turbulent convection in the → convective zone of stars, which is responsible for the driving of stellar → pulsation modes. In stars cooler than typically ~ 7 500 K (→ F-type stars and cooler), the stochastic excitation occurs in the convection envelope. In massive stars, it may develop either in the → convective core or in the convective layer beneath the → photosphere. Recent studies suggest that in → Be stars stochastic excitation takes place in the convective core. The stochastic waves can transport → angular momentum from the core to the surface. Fast rotation, as in Be stars, amplifies the stochastic excitation.

stochastic; → mode.

stochastic process
  فراروند ِ کاتورگین   
farâravand-e kâturgin

Fr.: processus stochastique   

Any process involving a sequence of random variables. The future evolution of a stochastic process is therefore described by probability distributions.

stochastic; → process.

stochastic self-propagating star formation
  دیسش ِ ستارگان با خود-توچش ِ کاتورگین   
diseš-e setâregân bâ xod-tuceš-e kâturgin

Fr.: formation d'étoiles par auto-propagation stochastique   

A mechanism that could be responsible for global → spiral structure in galaxies either by itself or in conjunction with spiral → density waves. In this mechanism, star formation is caused by → supernova-induced → shocks which compress the → interstellar medium. The → massive stars thus formed may, when they explode, induce further → star formation. If conditions are right, the process becomes self-propagating, resulting in agglomerations of young stars and hot gas which are stretched into spiral shaped features by → differential rotation. Merging of small agglomerations into larger ones may then produce large-scale spiral structure over the entire galaxy. The SSPSF model, first suggested by Mueller & Arnett (1976) was developed by Gerola & Seiden (1978). While the → density wave theory postulates that spiral structure is due to a global property of the galaxy, the SSPSF model examines the alternative viewpoint, namely that spiral structure may be induced by more local processes. The two mechanisms are not necessarily mutually exclusive, but they involve very different approaches to the modeling of galaxy evolution. The SSPSF gives a better fit than the density wave theory to the patchy spiral arms found in many spiral galaxies. However, it cannot explain → galactic bars.

stochastic; → self; → propagate; → star; → formation.

stoicheiology
  استویخیوشناسی   
stoyxiyošenâsi

Fr.: stoicheiologie   

1) The statement or discussion of the first principles of any science or art (1913 Webster).
2) Logic: The doctrine of the elementary requisites of mere thought (Sir W. Hamilton; 1913 Webster).

stoichiometry, → -logy.

stoichiometric
  استویخیوسنجیک   
stoyxiyosanjik

Fr.: stoechiométrique   

1) Of or pertaining to → stoichiometry.
2) Pertaining to or involving substances that are in the exact proportions required for a given reaction.

stoichiometry; → -ic.

stoichiometry
  استویخیوسنجی   
stoyxiyosanji

Fr.: stoechiométrie   

1) The branch of chemistry that studies chemical processes within the context of the laws of definite proportions and conservation of matter and energy.
2) The study of the quantitative relationships of two or more compounds in a chemical reaction.

From Gk. stoikheion "element, component, principle," Stoikheia "elements" (the title of Euclid's great collection of Gk. mathematics); loaned in Ar. and Pers. (9-th century A.D.) as ustuqus (اسطقس); akin to stoikhos "row, line, verse," steikhein "to go, march;" cf. Skt. stighnoti "rises, steps;" O.H.G. stigan; Ger. steigen; Goth. steigan "to go up, ascend;" O.E. stigan "to climb, go;" Ger. Steig "path;" O.E. stig "narrow path;" PIE base *steigh- "to go, rise, step, walk," + → -metry.

Stoyxiyosanji, from stoyxiyo loan from Gk., as above, + -sanji, → -metry.

stokes (st)
  استوکس   
stokes (#)

Fr.: stokes   

The unit of → viscosity in the → cgs system, cm2 s-1, equal to 10-4 m2 s-1.

After Sir George Gabriel Stokes (1819-1903), a British mathematician and physicist, who made important contributions to fluid dynamics, optics, and mathematical physics; → Stokes law; → Stokes parameter.

Stokes friction factor
  کروند ِ مالش ِ استوکس   
karvand-e mâleš-e Stokes

Fr.: facteur de friction de Stokes   

For the translational motion of a spherical body moving in a → viscous fluid, the proportionality factor between the uniform flow velocity far from the sphere and the drag force, provided no-slip boundary condition and small → Reynolds numbers: f = 6πηR, where η is the Reynolds number and R radius of the sphere.

Stokes; → friction; → factor.

Stokes law
  قانون ِ استوکس   
qânun-e Stokes (#)

Fr.: loi de Stokes   

1) Fluid mechanics: At low velocities, the frictional force on a spherical body moving through a fluid at constant velocity is equal to 6πRηv, where R is the radius of the sphere, η the fluid → viscosity, and v the velocity.
2) Spectroscopy: The wavelength of → luminescence excited by radiation is always greater than that of the exciting radiation.

Stokes; → law.

Stokes parameters
  پارامون‌های ِ استوکس   
pârâmunhâ-ye Stokes

Fr.: paramètres de Stokes   

Four parameters which are needed to fully describe the → polarization state of → electromagnetic radiation. They involve the maximum and minimum intensity, the ellipticity, and the direction of polarization. The four Stokes parameters are traditionally defined as follows:
I ≡ total intensity.
Q ≡ I0 - I90 = difference in intensities between → horizontal and → vertical  → linearly polarized components.
U ≡ I+45 - I-45 = difference in intensities between linearly polarized components oriented at +45° and -45° (or 135°).
V ≡ Ircp - Ilcp = difference in intensities between right and left → circularly polarized polarized components.

Stokes; → parameter.

stone
  سنگ   
sang (#)

Fr.: pierre   

The hard nonmetallic mineral or group of consolidated minerals either in mass or in a fragment of pebble or larger size. See also → rock.

O.E. stan; cf. O.N. steinn, Dan. steen, O.H.G., Ger. Stein; from PIE *stai- "stone," also "to thicken, stiffen" (cf. Skt. styayate "curdles, becomes hard;" Av. stay- "heap;" Gk. stear "fat, tallow," stia, stion "pebble").

Sang "stone, rock;" Mid.Pers. sang; O.Pers. aθanga-; Av. asenga- "stone;" PIE *aken-.

Stone Age
  عصر ِ سنگ   
asr-e sang (#)

Fr.: âge du fer   

A prehistoric period during which the main material used to make tools and weapons was stone. The Stone Age is usually divided into three separate periods (Paleolithic Period, Mesolithic Period, and Neolithic Period) based on the degree of sophistication in the fashioning and use of tools. The Paleolithic time period is by far the longest, beginning some two million years ago and ending around 10,000 BC to coincide with the end of the last ice age (Pleistocene epoch).

stone; → age.

stony meteorite
  شخانه‌ی ِ سنگی   
šaxân-ye sangi

Fr.: météorite pierreuse   

A meteorite composed largely of rock-forming (→ silicate) → minerals. Stony meteorites are the most abundant kind, about 95%, of all meteorites. They are divided into two groups: → chondrites and → achondrites.

stone; → meteorite.

<< < -es -iv -ti 21- A r abe abs abs acc acc acc act act ada adi adu aff age alc Alf ali all alp alt ama amp ana ang ang ann ano ant ant ape apo app aps arc Arg ari art ass ast ast ast atm ato att aur aut axi B r bac Bal Bar Bar Bay bec Ber Bet Bie bij bin bio bis bla bla blu blu bol Bor bou Bra bre bro Bug C-s cal Cam can car Car Cas cat cav cel cen cer Cha cha cha che cho cir cir cir cla clo clo clu 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 coo cor cor cor cos cos cos Cou cou Cra Cre cri cro cub cur cyc cyl dar dat daw de- Deb dec dec dee def deg del Den dep der det deu dew dic dif dif dil dip dir dis dis dis dis dis div dog Dop dou dra dua dus dwa dyn e-m ear ecl eco eff ein Ein elb ele ele ele ele Els emi emp ene enr env epi equ equ Eri est Euc eva evo exc exc exh exo exp exp ext ext f-n Fah fam fau fee Fer fib fil fin fir fix fle flu foc for for for fra fre fre fri fun fuz gal gal gal Gan gau GCN gen geo geo geo geo Gl glo gra gra gra gra gra gre gro GW1 hab hal han HAR haz hea hel hel Hen Her heu Hig Hil hol hop hor hou Hub Hum Hyd hyd hyd hyp hys ide ign ima imp imp inc inc ind ine inf inf inf inh INP ins ins int int int int Int int int int inv ion iri irr iso iso iso Jea Jos Jun K2 Kep key kin Kol lag lam Lan lar las lav lea leg len lev lig lim lin lin lin lis lob loc log lor low lum lun lun Lym Mac mag mag mag mag mag mai Mal mar mas mas mat max mea mea mee Men mer met met met mic mid Mil min Mir mix mod mod mol mon Mor mou mul muo mys nan nat nav nec Nep neu New New NGC nob nom non non nor not nuc nuc num Nyq obj obs obs oce oen OH omn opa ope opt opt opt orb ord Ori ort osc out ove oxy pal pan par Par par par pas pea Pen per per per per per pet pha pho pho pho phy pie Pit Pla pla pla pla ple Poi pol pol pol pol pop pos pos pow pre pre pre Pre pri pri pri pro pro pro pro pro pro Pro pub pul pyr qua qua qua qua Qui rad rad rad rad rad rad ram ran rat rea rec rec rec red ref ref reg reg rel rel rem rep res res res ret rev rho Rie rim riv rol Ros rot rul S a Sah san Sat sca Sch Sch scr sec sec sec sei sel sem sep set sha she sho sid sig sil sim sin sit sky slu sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spl spr sta sta sta sta sta ste ste sti sto str str sub sub sub sug sun sup sup sup sup sur syl syn sys tal Tay tel ten ter tex the the the thi tho thu tid tim tod top tot tra tra tra tra tri tri tro tru tur twi Typ UFO ult unc uni uni uni upg ura uti val var vec vel ver ver vig vir vis voc von wak Was wav wax wea wei whi Wie win WN6 wom X-r yel you zer zod > >>