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 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
no hair theorem
  فربین ِ بی‌مویی، ~ کچلی   
farbin-e bimu-yi, ~ kacali

Fr.: théorème de calvitie   

There are only three parameters that can be applied by an outside observer relating to a → black hole: → mass, → electric charge, and → angular momentum. The collapse of a star into a black hole wipes out all other details of its structure, and the observer can never discover any other properties of the star which formed the black hole. In other words, none of its characteristics leave any trace outside the black hole, and that is what is meant by "hair."

No, M.E., from O.E. na "never, no," cognate with Pers. na, nâ, → non-; → hair; → theorem.

Farbin, → theorem; bimuyi, noun from bimu "without hair," from bi- "without" (→ in-) + mu, → hair.
Kacali "baldness," from kacal "bald," also "crooked, bandy-legged," from kajal, from kaj "crooked, curved, bent" + → -al; probably unrelated to kal "bald," → colure.

Noachian era
  دوران ِ نوحیانه   
dowrân-e Nuhiyâné

Fr.: ère noachienne   

>Noachian era = dowrân-e Nuhiyâné     دوران ِ نوحیانه

Fr.: ère noachienne

The oldest geological era on Mars, which started from the planet's birth and lasted until about 3.8 billion years ago. Features such as dried-up river valleys and delta features suggest that the climate may have been warmer and wetter. It is believed also that lakes and oceans could have existed. → Amazonian era; → Hesperian era.

The oldest geological era on Mars, which started from the planet's birth and lasted until about 3.8 billion years ago. Features such as dried-up river valleys and delta features suggest that the climate may have been warmer and wetter. It is believed also that lakes and oceans could have existed. → Amazonian era; → Hesperian era.

Noachian, named for → Noachis Terra "Land of Noah;" → era.

Noachis Terra
  زمین ِ نوحیانه   
zamin-e Nuhiyâné

Fr.: Noachis Terra   

An extensive southern terrain of the planet Mars. One of the oldest terrains on Mars, it lies roughly between the latitudes -20° and -80° and longitudes 30° west and 30° east.

L. Noachis Terra "Land of Noah."

Zamin "land," → earth; Nuhiyâné adj. of Nuhi "related to Nuh," from Nuh (نوح) "Noah."

noble gas
  گاز ِ هوپد   
gâz-e huped

Fr.: gaz rare   

A gaseous chemical element that does not readily enter into chemical combination with other elements. Examples are helium, argon, krypton, xenon, and radon. Same as → inert gas.

Noble, from O.Fr. noble, from L. nobilis "well-known, famous, of superior birth," earlier gnobilis, literally "knowable," from gnoscere "to come to know" (Fr. connaître; Sp. conocer); cognate with Pers. šenâxtan "to know, discern, distinguish, be acquainted with;" Mid.Pers. šnâxtan, šnâs- "to know, recognize," dânistan "to know;" O.Pers./Av. xšnā- "to know, learn, come to know, recognize;" cf. Skt. jñā- "to recognize, know," jānāti "he knows;" Gk. gignoskein "to know, think, judge;" P.Gmc. *knoeanan; O.E. cnawan; E. know; Rus. znat "to know;" PIE base *gno- "to know;" → gas.

Gâz, → gas; huped "noble," from Mid.Pers. hupid "noble," from hu- "good, well" (Mid.Pers. hu-; O.Pers. hu- "good, well" (ukāra- "having good people"); Av. hu-, hū- "well, good, beautiful" (hu-kərp- "well-shapen," hūxta- "well spoken," hu-manah- "good-minded"); cf. Skt. su- "good" (svasti "well-being, good luck," sumánas- "good-minded," sūktá- "well spoken"); L. from Gk. eu "well," combining form of eus "good" (hu-gies "healthy"); Gallic su-; O.S. su-; Welsh hy-; PIE base *su-) + pid "father," variant of pidar; Mod.Pers. pedar "father" (O.Pers. pitā- "father;" Av. patar-; Skt. pitár-; Gk. pater; L. pater, O.H.G. fater).

nock
  سوفار   
sufâr (#)

Fr.: entaille, encoche   

The end part of an → arrow having a notch for holding the bowstring.

M.E. nok(ke); of uncertain origin; cf. Swedish nock "notch;" also M.L.G. nokk, Dutch nok "tip of a sail."

Sufâr "the notch in the arrow which receives the string," also "the eye of needle," related to softan, sombidan "to pierce;" Mid.Pers. sôftan "to pierce, bore;" cf. Pashtu suray, Wakhi sərv "hole, cavity," Munji surv "hole," Yidgha surv, Kurd. sontin; Proto-Ir. sup, sub, sump, sumb "to pierce."

noctilucent cloud
  ابر ِ شب‌تاب   
abr-e šabtâb

Fr.: nuage nocturne lumineux   

The highest clouds in the Earth's atmosphere, at altitudes between 75 and 90 km. They resemble thin cirrus clouds with a bluish or silverish color, and are visible only during twilight.

From nocti- combining form of L. nox, → night, + L. lucent p.p. of lucere "to shine," from luxlight; → cloud.

Abr, → cloud, + šabtâb "noctilucent," from šab, → night, + tâb present stem of tâbidan "to shine," → luminous.

nodal
  گرهی   
gerehi (#)

Fr.: nodal   

Relating to or of the nature of a node.

node; → -al.

nodal line
  خط ِ گره‌ها   
xatt-e gerehhâ

Fr.: ligne des noeuds   

The line connecting the ascending and descending nodes of an orbit.

nodal; → line.

nodal point
  نقطه‌ی ِ گرهی   
noqte-ye gerehi

Fr.: point nodal   

Any of the two points on the → axis of a → lens system, such that if the → incident ray passes through one, travelling in a given direction, the → emergent ray passes the other in a parallel direction.

nodal; → point.

nodal regression
  پسرفت ِ گرهی   
pasraft-e gerehi

Fr.: regression nodale   

For a ring inclined to the planet's equator, the points at which the ring crosses the equator (nodes) slowly move around the planet (regress) in a direction opposite to that of the ring's orbital motion. (Ellis et al., 2007, Planetary Ring Systems, Springer).

nodal; → regression.

node
  گره   
gereh (#)

Fr.: nœud   

1) A point of zero → amplitude in a system of → stationary waves. See also → antinode.
2) A → junction point in a network.
3) Same as → orbital node; see also → lunar node.
4) In → graph theory, same as → vertex.

From L. nodus "knot."

Gereh "knot," from Mid.Pers. grih "knot;" Sogdian γr'nš "knot, bond, joining;" Khotanese grantha- "knot;" cf. Skt. granthi- "knot."

nodical month
  ماه ِ گرهی، ~ گوزهری   
mâh-e gerehi (#), ~ gowzahri (#)

Fr.: mois draconitique   

The time interval between two successive passages of the Moon through its ascending node (27.212220 days, i.e., 27 days 5 hours 5 minutes 35.8 seconds). Nodical month is important for predicting eclipses. Also called → draconic month.

Nodical adj. of → node; → month.

Mâh, → month; gerehi, adj. of gereh, → node; gowzahridraconic month.

Noether's theorem
  فربین ِ نوتر   
farbin-e Noether

Fr.: théorème de Noether   

A → symmetry in a physical system leads to a → conserved quantity. For example, symmetry under → translation corresponds to conservation of → momentum, symmetry under → rotation to conservation of → angular momentum, and symmetry in → time to conservation of → energy. The Noether symmetry theorem is a fundamental tool of modern theoretical physics and the calculus of variations, allowing to derive conserved quantities from the existence of variational symmetries.

Named in honor of the German-American woman mathematician Amalie Emmy Noether (1182-1935), who published the theorem in 1918 ("Invariante Variationsprobleme," Nachr. D. König. Gesellsch. D. Wiss. Zu Göttingen, Math-phys. Klasse 1918: 235-257).

noise
  نوفه   
nufé (#)

Fr.: bruit   

1) The → random → fluctuations that are always associated with a measurement that is repeated many times over. Any unwanted disturbance, random or → systematic, which contaminates the → signal from an object under study. More specifically:
2) Electronics: An undesired signal within the useful frequency band.
3) Acoustics: Any extraneous sound tending to interfere with the perception of wanted sound.
See also:
atmospheric noise, → background noise, → cosmic radio noise, → dark current noise, → Galactic radio noise, → Johnson-Nyquist noise, → noise source, → noise temperature, → noise voltage, → noise-equivalent power, → photon noise, → quantum noise, → radio noise, → random noise, → readout noise, → receiver noise, → Schottky noise, → shot noise, → signal-to-noise ratio, → speckle noise, → stationary noise, → system noise, → thermal noise, → white noise.

Noise, of obscure origin; it has been related to O.Fr. noise "uproar, brawl," apparently from L. nausea "disgust, annoyance," literally "seasickness." Alternatively the O.Fr. word is traced to L. noxia "hurting, injury, damage."

Nufé "noise," related to Mod.Pers. noyidan "to cry loud, lament," navidan, nâvidan "to lament," noyé, nôyah "plaint, mown," navâ "sound, song," (with prefix *uz-) zenudan, zenav-, zonudan "to wail," Ossetic niwyn/newun "to howl," O.Khotanese nuva- "to make a noise," Yaqnâvi nuyok "crying, howling," novva "sound," Shahmirzâdi nâv- "to cry; cf. Skt. nav- "to sound loudly, roar," náva- "show of joy or triumph;" L. nuntius "messenger," adnuntiare "to annoince;" Tocharian AB nu- "to roar, PIE *neu- "to shout".

noise source
  خن ِ نوفه   
xan-e nufé

Fr.: source de bruit   

An electronic device designed to generate known amounts of radio noise in order to test and calibrate the receivers of radio telescopes.

noise; → source.

noise temperature
  دمای ِ نوفه   
damâ-ye nufé

Fr.: température de bruit   

A means for specifying the noise generated as unwanted → electromagnetic radiation in a receiver system or one of its components. It is usually measured in terms of the equivalent temperature in a → Rayleigh-Jeans spectrum. Noise temperature is used mainly in radio astronomy.

noise; → temperature.

noise voltage
  ولتاژ ِ نوفه   
voltâž-e nufé

Fr.: voltage de bruit   

Fluctuations of electric potential in a physical system due to spontaneous disturbances in the system.

noise; → voltage.

noise-equivalent power
  توان ِ هم‌ارز ِ نوفه   
tavân-e ham-arz-e nufé

Fr.: puissance équivalente de bruit   

A measure of the sensitivity of an electronic detector, defined as the power input to the detector that will create a signal to noise ratio of one for an integration time of half a second.

noise; → equivalent; → power.

nomenclature
  نامگذاری   
nâmgozâri (#)

Fr.: nomenclature   

A set or system of names or terms assigned to objects or items in a particular science or art.

From Fr. nomenclature, from L. nomenclatura "calling of names," from nomenclator, variant of nomenculator "one who announces names, namer," from nomen, → name, + calator "caller," from calare "to call."

Nâmgozâri, from nâm, → name, + gozâri, verbal noun of gozâštan "to place, put; to allow, let," related to gozaštan "to pass, proceed, go over;" Mid.Pers. vitar- "to let pass, lead; to pass;" O.Pers. vitar- "to go across," viytarrayam "I put across;" Av. tar- "to cross over," vī-tərəta- "taken away, isolated;" ultimately Proto-Ir. *ui-tar-.

nominal
  نامنال   
nâmenâl

Fr.: nominal   

1) Of, pertaining to, or constituting a name or names, a noun or nouns.
2) Describing a value quoted for commodity, expectation, or its current estimate, as opposed to the actual value. → nominal value.
3) Within acceptable limits; as expected.
4) a) Grammar: Relating to a noun or to any word or word group that functions as a noun. b) A word which differs from a noun but functions as one.

From L. nominalis "pertaining to a name or names," from nomen "name," cognate with Pers. nâm, as below.

Nâmenâl, from nâmen, from O.Pers./Av.nâman-, → name, + suffix -al.

<< < -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 > >>