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 -iv -ti 21 a p abe abs abs aca acc acc acr act ada adh Adr aer AGB air Alf Alg all alp alt AM amo ana And ang ani ano Ant Ant apa apo app app Ara Arc ari Arr ash ass ast ast asy atm ato att aut ave axi Bab bal Bal bar bar bea Bek Bes bia Big bin bin bip biv bla bli blu Boh Bol Bos bou bra bri bro buo cal cal can cap car Car cat cat CCD Cen cen CH cha cha che Che chr cir cir cit 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 con Cop Cor cor cor cos cos cou cou Cow cre cri cro cry cur cya Cyg dan dar dat de- deb dec dec ded def deg del dem den dep des det dev dia dif dif dih dio Dir dis dis dis dis dis dis DO don dou dow dro dur dwa dyn Dys ear ebb ecl edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ equ esc eth Eur Eve exa exc exe exi exp exp ext ext ext fac fal far fed Fer fer fie fin fir fis fla flo flu fol for for fou fra fre Fre fro fut G-t gal gal gam gas Gau Gem gen geo geo geo gia Gli Gol gra gra gra gra gre gri gui H I Hag hal har hat He- hea hel Hel her Hes hie hig his hom hor hot Hub Hug hur hyd hyd hyg 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 Io ion iro isl iso iso Jac jet jud jur Kel Kep kil Klo Kui Lag lam Lap Lar lat law lea len lep Lib lig lim lin lin Lio lit loc LOF lon Lor low lum lun Lup Lyo mac mag mag mag mag mag mai man Mar mas mas mat Max mea mec Meg Mer Mer met met Met mic Mid Mil min Mir mit mod mod mol mon Mor mou mul mul mys nan Nat nau nec neo neu nev New NGC no nom non non nor not nuc nuc num nut obj obs obs occ ocu oft ome Oor ope opp opt opt orb ord ori ort osc out ove oxi pai pan par par par par pas pea pen per per per per Per per pha phi pho pho pho phy pio Pla pla pla pla Pla plu Poi pol pol pol poo pos pos pot pra pre pre pre pre pri pri pro pro pro pro pro Pro pro pse pul pur qua qua qua qua que rac rad rad rad rad rad rad 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 Rus Sac sal sat sca sca Sch sci Scu sec sec Sed sel Sel sen ser Sex Sha she sho sid sig sil sim sin siz sla Sma sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spi spr squ sta sta sta sta ste ste ste Sto Str str str sub sub suc sun sup sup sup sup sur swa syn syn tab tar tek tem ter tes the the the the Tho thr tid tim Tis Too Tor tra tra Tra tra tra tri tri tru Tul tur two Typ ult un- und uni uni unk upp Urc utt val var vec vel ver vib vio vir vis voi vor wan wat wav wax wea Wei whi Wil win WN9 wor X-r yel you zer zod > >>

Number of Results: 13048 Search : far
light-gathering power
  توان ِ گرد‌آوری ِ نور   
tavân-e gerdâvari-ye nur (#)

Fr.: pouvoir collecteur de lumière   

The most important function of an astronomical telescope, which is directly related to the area (or to the square of the diameter) of the main mirror or lens.

light; gathering, from O.E. gadrian, gædrian "to gather, collect;" → power.

Tavân, → power; gerdâvari, verbal noun of gerd âvardan, from gerd "round; around" (Mid.Pers. girt "round, all around," O.Iranian *gart- "to twist, to wreathe," cf. Skt. krt "to twist threads, spin, to wind, to surround," kata- "a twist of straw;" Pali kata- "ring, bracelet;" Gk. kartalos "a kind of basket," kyrtos "curved") + âvardan "to bring," Mid.Pers. âwurtan, âvaritan; Av. ābar- "to bring, to possess," from prefix ā- + Av./O.Pers. bar- "to bear, carry," bareθre "to bear (infinitive)," bareθri "a female that bears (children), a mother;" Mod.Pers. bordan "to carry;" Skt. bharati "he carries;" Gk. pherein; L. fero "to carry;" nur, → light.

light-second
  نور-ثانیه، ثانیه‌ی ِ نوری   
nur-sâniyé, sâniye-ye nuri

Fr.: second-lumière   

The distance travelled by light in free space in one second. It is equivalent to 2.997924580 × 108 m or 2.998 × 105 km. This unit of length is mainly used in astronomy, telecommunications, and relativistic physics. Some quantities expressed in this unit are as follows. The mean diameter of the Earth: about 0.0425 light-seconds. The average distance from the Earth to the Moon: about 1.282 light-seconds. The diameter of the Sun: about 4.643 light-seconds. The average distance from the Earth to the Sun: 499.0 light-seconds.

light; → second.

light-time
  نور-زمان، زمان ِ نوری   
nur-zamân, zamân-e nuri (#)

Fr.: temps-lumière   

The time it takes for light, travelling at about 300 000 km per second, to travel a certain distance.

light; → time.

light-travel distance
  اپست ِ سفر ِ نور   
apest-e safar-e nur

Fr.: distance du voyage de la lumière   

The distance traversed by a photon between the time it is emitted and the time it reaches the observer. It is also referred to as the → look-back time.

light; → travel; → distance.

light-year
  نور-سال، سال ِ نوری   
nur-sâl (#), sâl-e nuri (#)

Fr.: année-lumière   

The distance that light travels in one year at about 300,000 km per second, i.e. 9.5 x 1012 km. It is equal to about 63,000 → astronomical units. See also → parsec.

light; → year.

lightguide
  نوربَر   
nurbar

Fr.: faisceau de fibres optiques; guide d'ondes optique   

A bundle of optical fibers arranged randomly for the purpose of transmitting energy, not an image.

light; → guide.

lightlike
  نورسان   
nursân

Fr.: genre lumière   

Of, pertaining to, or describing an → event on the → light cone.

light; → -like.

lightlike interval
  اندروار ِ نورسان   
andarvâr-e nursân

Fr.: intervalle genre lumière   

The space-time interval between two events if it is zero, i.e. ds2 = 0.

lightlike; → interval.

lightning
  آذرخش   
âzaraxš (#)

Fr.: foudre   

A → flash of light produced by an → electric discharge in response to the buildup of an → electric potential between → cloud and → Earth's surface, or between different portions of the same cloud.

Lightning, pr.p. of lightnen "make bright," extended form of O.E. lihting, from leht, → light.

Âzaraxš, from âzar "fire," variants âtaš, taš (Mid.Pers. âtaxš, âtur "fire;" Av. ātar-, āθr- "fire," singular nominative ātarš-; O.Pers. ātar- "fire;" Av. āθaurvan- "fire priest;" Skt. átharvan- "fire priest;" cf. L. ater "black" ("blackened by fire"); Arm. airem "burns;" Serb. vatra "fire;" PIE base *āter- "fire") + raxš "lightning, reflection of light," raxšidan "to shine, flash," variant deraxš, deraxšidan "to shine, radiate" (O.Pers. raucah-, Av. raocah- "light" (cf. Skt. roka- "brightness, light," Gk. leukos "white, clear," L. lux "light" (also lumen, luna), E. light, Ger. Licht, Fr. lumière; PIE base *leuk- "light, brightness"); cognate with Mod.Pers. words ruz "day," rowšan "bright, clear," foruq "light," and afruxtan "to light, kindle").

likelihood
  شدواری   
šodvâri

Fr.: vraisemblance   

1) The state of being likely or probable; a probability or chance of something.
2) In technical language likelihood is not synonymous for probability. Same as → likelihood function.

From → likely + -hood a suffix denoting state, condition, character, nature, etc., from M.E. -hode, -hod, O.E. -hād (cf. Ger. -heit).

Šodvâri, noun of šodvâr, → likely.

likelihood function
  کریای ِ شدواری   
karyâ-ye šodvâri

Fr.: fonction de vraisemblance   

A function that allows one to estimate unknown parameters based on known outcomes. Opposed to → probability, which allows one to predict unknown outcomes based on known parameters. More specifically, a probability refers to the occurrence of future events, while a likelihood refers to past events with known outcomes.

likelihood; → function.

likely
  شدوار   
šodvâr

Fr.: vraisemblable   

Probably or apparently destined; having a high probability of occurring or being true.

Perhaps from O.N. likligr "likely," from likr "like" (adj.).

Šodvâr, from šod past stem of šodan "to become, to be, to be doing, to go, to pass" + -vâr a suffix with several meanings "resembling, like, in the manner of; having, endowed with." The first element from Mid.Pers. šudan, šaw- "to go;" Av. šiyav-, š(ii)auu- "to move, go," šiyavati "goes," šyaoθna- "activity; action; doing, working;" O.Pers. šiyav- "to go forth, set," ašiyavam "I set forth;" cf. Skt. cyu- "to move to and fro, shake about; to stir," cyávate "stirs himself, goes;" Gk. kinein "to move;" Goth. haitan "call, be called;" O.E. hatan "command, call;" PIE base *kei- "to move to and fro."

limb
  لبه   
labé (#)

Fr.: bord   

1) The outer edge or border of the apparent disk of a celestial body. → limb brightening, → limb darkening.
2) The raised edge of the mater of a → planispheric astrolabe, bearing a scale divided into 360°. The limb is the reference against which the rete is rotated in the computation process so that the planispheric astrolabe will simulate the sky's appearance on a given day at a specific hour. Vice versa, the limb can be configured from the observation of the altitude of an celestial body on the horizon. In that case, the limb will indicate an angle that, thanks to the hour scale on the back, can be converted into the hour of day or night (online museo galileo, VirtualMuseum).

From L. limbus "border, hem, fringe, edge," cognate with Skt. lambate "hangs down."

Labé "limb, edge," from lab "lip;" Mid.Pers. lap; cognate with L. labium, E. lip; Ger. Lefze.

limb brightening
  روشنش ِ لبه   
rowšaneš-e labé

Fr.: embrillancement centre-bord   

An observed increase in the intensity of radio, extreme ultraviolet, or X-radiation from the Sun from its center to its limb.

limb; → brightening.

limb darkening
  تاریکش ِ لبه   
târikeš-e labé

Fr.: assombrissement centre-bord   

An apparent decrease in brightness of the Sun near its edge as compared to its brightness toward the center. Limb darkening is readily apparent in photographs of the Sun. The reason is that when we look toward the disk's center we look into deeper and hence hotter layers along the line of sight. Toward the limb, we get radiation from higher and hence cooler and less bright layers of the → photosphere. Limb darkening has been detected in the case of several other stars. A similar phenomenon occurs in → eclipsing binaries where the effect of limb darkening on one or both components manifests itself in the shape of the system's → light curve.

limb; → darkening.

lime
  آهک   
âhak (#)

Fr.: chaux   

A white or grayish-white substance obtained by burning → limestone, used in mortars, plasters, cements, and in the manufacture of steel, paper, glass, and various chemicals of calcium.

M.E., O.E. lim; akin to Du. lijm, Ger. Leim, O.N. lim "glue;" L. limus "slime."

Âhak, probably a variant of xâk, → soil.

limestone
  سنگ ِ آهک   
sang-e âhak (#)

Fr.: castine, calcaire    

A → sedimentary rock composed principally of calcium carbonate. Limestone is usually formed from shells of once-living organisms or other organic processes, but may also form by inorganic precipitation.

lime; → stone.

limit
  حد   
hadd (#)

Fr.: limite   

1) General: The final, utmost, or furthest → boundary or → point as to extent, amount, continuance, procedure, etc.
2a) Math.: Of a → sequence, a → number which is approached ever more closely, but never reached, by the successive terms of a convergent infinite sequence.
2b) Of a → variable, a constant C which has the property with respect to some variable V that, as the variable approaches C in value (according to some formula), the numerical difference (C - V) between the constant and the variable diminishes toward 0 but is always greater than 0.

From O.Fr. limite "a boundary," from L. limitem (nom. limes) "a boundary, embankment between fields, border," related to limen "threshold."

Loan from Ar. Hadd "limit, term."

limited
  حدمند   
haddmand

Fr.: limité   

Confined within limits; restricted or circumscribed.

Adj. of → limit.

limiting magnitude
  برز ِ حد   
borz-e hadd

Fr.: magnitude limite   

The faintest magnitude reachable by an instrument.

limit; → magnitude.

<< < -es -iv -ti 21 a p abe abs abs aca acc acc acr act ada adh Adr aer AGB air Alf Alg all alp alt AM amo ana And ang ani ano Ant Ant apa apo app app Ara Arc ari Arr ash ass ast ast asy atm ato att aut ave axi Bab bal Bal bar bar bea Bek Bes bia Big bin bin bip biv bla bli blu Boh Bol Bos bou bra bri bro buo cal cal can cap car Car cat cat CCD Cen cen CH cha cha che Che chr cir cir cit 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 con Cop Cor cor cor cos cos cou cou Cow cre cri cro cry cur cya Cyg dan dar dat de- deb dec dec ded def deg del dem den dep des det dev dia dif dif dih dio Dir dis dis dis dis dis dis DO don dou dow dro dur dwa dyn Dys ear ebb ecl edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ equ esc eth Eur Eve exa exc exe exi exp exp ext ext ext fac fal far fed Fer fer fie fin fir fis fla flo flu fol for for fou fra fre Fre fro fut G-t gal gal gam gas Gau Gem gen geo geo geo gia Gli Gol gra gra gra gra gre gri gui H I Hag hal har hat He- hea hel Hel her Hes hie hig his hom hor hot Hub Hug hur hyd hyd hyg 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 Io ion iro isl iso iso Jac jet jud jur Kel Kep kil Klo Kui Lag lam Lap Lar lat law lea len lep Lib lig lim lin lin Lio lit loc LOF lon Lor low lum lun Lup Lyo mac mag mag mag mag mag mai man Mar mas mas mat Max mea mec Meg Mer Mer met met Met mic Mid Mil min Mir mit mod mod mol mon Mor mou mul mul mys nan Nat nau nec neo neu nev New NGC no nom non non nor not nuc nuc num nut obj obs obs occ ocu oft ome Oor ope opp opt opt orb ord ori ort osc out ove oxi pai pan par par par par pas pea pen per per per per Per per pha phi pho pho pho phy pio Pla pla pla pla Pla plu Poi pol pol pol poo pos pos pot pra pre pre pre pre pri pri pro pro pro pro pro Pro pro pse pul pur qua qua qua qua que rac rad rad rad rad rad rad 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 Rus Sac sal sat sca sca Sch sci Scu sec sec Sed sel Sel sen ser Sex Sha she sho sid sig sil sim sin siz sla Sma sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spi spr squ sta sta sta sta ste ste ste Sto Str str str sub sub suc sun sup sup sup sup sur swa syn syn tab tar tek tem ter tes the the the the Tho thr tid tim Tis Too Tor tra tra Tra tra tra tri tri tru Tul tur two Typ ult un- und uni uni unk upp Urc utt val var vec vel ver vib vio vir vis voi vor wan wat wav wax wea Wei whi Wil win WN9 wor X-r yel you zer zod > >>