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 217 a- abe abs abs acc acc ach act act ada adi adv aff agg Alc Alf ali all alp alt Ama amp ana ang ang ann ano ant ant ape apo app aps arc arg arm art ass ast ast ast atm ato att aur aut axi B-t bai Bal bar bar Be bee Bes bi- bif bin bin bio bis bla bli blu Boe Bol bor bou bra bri Bro bum CAI cal Can cap car car cat cat CCD Cel cen CGS cha cha che che 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 coo cor cor cor cos cos cos cou cov cra cri cro cry cum cur cyc d'A dar dat DC dea dec dec dec def def deh Del den dep des det dev dia dif dif dif dim dip dir dis dis dis dis dis div dom dou dou dri dup dus dyn dyn ear eas ecl Edd eff Ein Ekm ele ele ele ele ell emb emi enc ene ent eph equ equ equ eru eth eup eve EX exc exe exi exo exp ext ext ext fac fal far fec Fer fer fie fin fir fis fla flo flu fog for for Fou fra fre Fre Fro fus G-t gal gal Gam gas Gau Gem gen geo geo geo gia gla gol gra gra gra gra Gre Gre gui H a haf Hal har har He- hea hel Hel her Her hie hig his hom hor hot Hub Hug hur hyd hyd hyl hyp ice ide ima imp imp imp inc ind ind ine inf inf Inf inj InS ins int int int int int int int int inv inv ion iro Isl iso iso Jac jet jud jur Kel Kep kil kly L d Lag lam Lap lar lat law Lea len lep lib lig lin lin lin liq lit loc log lon Los low lum lun Lut Lyr mac mag mag mag mag mag maj man Mar mas mas mat mea mec mem mer mes met met met mic mid mil min Mir Miz mod mol mon moo MOS mul mul mut nai nas nat neb neg Neu neu New New Nih noi non non non nor nuc nuc nul nut obj obl obs occ oct off old one ope opp opt opt orb ord org Ori osc oth ove oxi pac Pal par par Par par pas Pau Pel per per per per per per pha phi pho pho pho phy pip Pla pla pla pla pla Plu Poi pol pol pol pop pos pos pot Pra pre pre pre Pri pri pri pro pro pro pro pro pro pro Pto pul puz qua qua qua qua qui rad rad rad rad rad rad rai ran Ras Ray rea rec rec rec red red ref reg reg rel rel rel rep res res res res rev rhe Rie Rig Rit roe Ros rot Ruf Ryd Sag sam sat sca sca Sch Sco sec sec sec seg sel sem sen set sha SHB sho sib sie sil sim sin sit sky slo sno sod sol sol sol sol sor sou Spa spa spe spe spe sph spi Spi spr sta sta sta sta sta ste ste Ste sto str str sub sub sub suf sun sup sup sup sup sur swo syn sys tak Tay Tel ten ter tet the the the thi Tho thu tid tim toa top tot tra tra tra tra tri tri tro Tru tur twi Typ UBV ult unb uni uni uni up ura uti val var vec Vel ver ver vig vir vis VLT vol wad was wav wav wea wei Whe Wie win WN5 Wol X-r yea You zer zod > >>

Number of Results: 12929 Search : far
Be star
  ستاره‌یِ Be   
setâre-ye Be

Fr.: étoile Be   

A hot star of → spectral type B showing → Balmer lines in emission. Be stars are fast rotators (spinning at about 200 km/sec) and have strong → stellar winds with important → mass loss.

B, referring to the spectral type; e for emission lines; → star.

beam
  تابه   
tâbé (#)

Fr.: 1) faisceau, 2) lobe, 3) tache de diffraction   

1) A collection of nearly parallel → light  → rays or a concentrated stream of → particles. See also → beam of light.
2) The area of the sky being observed at any one time by a → radio telescope.
3) The size of the → diffraction pattern; synonymous with point spread function.

M.E. beem, from O.E. beam "tree;" akin to O.H.G boum "tree," Ger. Baum.

Tâbé, from tâb; tâbidan "light; to shine" + noun suffix.

beam efficiency
  کار‌آیی ِ تابه   
kârâi-ye tâbé

Fr.: efficacité de lobe   

A parameter indicating the quality of an antenna as a direction measuring device. It is given by the ratio of the total received power contained in the main beam of an antenna to the total power (including the sidelobes); the same as main beam efficiency. See also → beamwidth.

beam; → efficiency.

beam of light
  تابه‌ی ِ نور   
tâbe-ye nur (#)

Fr.: faisceau lumineux   

A relatively large bundle of → rays of light. See also → pencil of light.

beam; → light.

beam of particles
  تابه‌ی ِ ذره   
tâbe-ye zarré

Fr.: faisceau de particules   

A narrow unidirectional flow of particles

beam; → particle.

beam splitter
  فاقگر ِ تابه   
fâqgar-e tâbé

Fr.: lame séparatrice   

A partially reflecting mirror which permits a part of the light beam to pass through and reflects the rest.

beam; splitter, from to split, from M.Du. splitten, from P.Gmc. *spl(e)it-, PIE *(s)plei- "to split, splice."

Fâqgar, from fâq "split, breach, division" + tâbébeam.

beam switching
  دگربانی ِ تابه   
degarbâni-ye tâbé

Fr.: permutation de lobe   

In single dish radio astronomy, any technique which forms the difference of signals received from two (or more) pointings on the sky without physically moving the main reflector of the antenna. By rapidly forming differences between sky positions that do and do not contain astronomical sources, beam switching can minimize the corruption of spectral baselines by non-idealities in the instrumental frequency response, or of continuum observations by atmospheric fluctuations.

beam; → switching.

beamwidth
  تابه-پهنا   
tâbe-pahnâ

Fr.: largeur de lobe   

The angle between the two directions in the main beam at which the power response has fallen to half its maximum value. → beam efficiency.

From → beam + → width.

Tâbe-pahnâ, from tâbé, → beam, + pahnâ "width," → broad.

beat
  زنش   
zaneš (#)

Fr.: battement   

The periodic and alternatively strengthening and weakening of two waves of similar frequencies when they interfere with one another. In particular, the soft and loud sounds created by the interference of two sound waves of similar frequencies.

M.E. beten, from O.E. beaten, from P.Gmc. *bautan; IER *bhau- "to strike."

Zaneš, noun from zan- present tense stem of zadan "to beat, strike" + verbal noun suffix. Zadan from Mid.Pers. zatan, žatan; O.Pers./Av. jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"); cf. Skt. han- "to strike, beat" (hantar- "smiter, killer"); Gk. theinein "to strike;" L. fendere "to strike, push;" Gmc. *gundjo "war, battle;" PIE *gwhen- "to strike, kill."

beat Cepheid
  کِفِیءوسی ِ زنشی   
kefeusi-ye zaneši

Fr.: céphéide à battement   

A Cepheid variable in which two or more almost identical periods of variability pass into and out of phase with each other, producing periodic amplitude fluctuations in their light curves. Beat periods are typically about 2 hours.

beat; → Cepheid.

beat frequency
  بسامد ِ زنش   
basâmad-e zaneš

Fr.: fréquence de battement   

One of the frequencies that results from the combination of two waves of slightly different frquencies. A beat frequency is equal to the absolute value of the difference between the two frequencies. An unknown frequency can be determined by beating it with a reference frequency. More specifically, when the two frequencies are superimposed, the phase difference will change with time and wave interference alternate between constructive and destructive. The alterations of intensity brings about a beat frequency.

beat; → frequency.

Beaufort scale
  مرپل ِ بوفورت   
marpel-e Beaufort

Fr.: échelle de Beaufort   

A system for estimating and reporting wind speeds which has 13 standardized categories and associated descriptions. The Beaufort scale ranges from 0 for complete calm to 12 for a cyclone. In this scale, the wind speed (in km/h) equals 3B1.5, where B is the Beaufort number of the wind. The scale was originally devised for use at sea but has subsequently been modified for use over land.

Named after Admiral Sir Francis Beaufort (1774-1857), who introduced the first version of the system in 1805; → scale.

beauty
  زیبایی   
zibâyi (#)

Fr.: beauté   

A combination of qualities that pleases the mind.

M.E. be(a)ute, from O.Fr. beautez, beltet "beauty, seductiveness, beautiful person" from V.L. bellitatem (nominative bellitas) "state of being handsome," from L. bellus "pretty, charming."

Zibâyi, from zibâ "beautiful," related to zib "beauty, elegance, ornament," zibidan "to suit, to adorn."

beaver
  بیدستر   
bidastar (#)

Fr.: castor   

A large, amphibious rodent of the genus Castor, having sharp incisors, webbed hind feet, and a flattened tail, noted for its ability to dam streams with trees, branches, etc. (Dictionary.com).

M.E. bever, O.E. beofor, befor; cognate with Ger. Biber; Av. bawra-, bawri- "beaver" (Mid.Pers. bawrak "beaver"); Skt. babhrav- "reddish-brown," babhrus- "mangoose," L. fiber "beaver" (Fr. bièvre "River of Beavers"); O.H.G. biorr; Lith. bêbrus; Rus. bobr "beaver."

Bidastar "beaver," of unknown origin.

because
  زیرا   
zirâ (#)

Fr.: parce que   

For the reason that; on account of.

M.E. bi cause "by cause," from O.E. bi "by" (akin to Du. bij, O.H.G. bi, Ger. bei, Goth. bi) + → cause.

Zirâ, variants azirâ, zirâk, azirâk, from Mid.Pers. êt rây cê or ê(t) râd cê "because," literally "this reason why;" from êd "this" (O.Pers. aita; Av. aēta "this;" cf. Skt. etá); rây, → reason; "what" (O.Pers/Av. ci- "what, any," collateral stem to ka- "who?, what?;" cf. Skt. ka-; Gk. po-; L. quo-; E. what, who; PIE *qwos/*qwes).

Becklin-Neugebauer object
  بر‌آخت ِ بکلین-نیوجباؤر   
barâxt-e Becklin-Neugebauer

Fr.: objet de Becklin-Neugebauer   

A compact infrared source in the Orion molecular cloud (OMC-1). It is thought to be a very dusty compact H II region surrounding a young B0 or B1 star.

After Eric Becklin (1940-), and Gerry Neugebauer (1932-) who discovered the object in 1967; → object.

become
  شدن   
šodan (#)

Fr.: devenir   

To come, change, or grow to be.

M.E. becumen; O.E. becuman "happen, come about," also "meet with, arrive;" akin to Du. bekomen, O.H.G. biqueman "obtain," Ger. bekommen, Goth. biquiman; from be- a prefix denoting several meanings, and → come.

Šodan "to become, to go, to pass, to change," from Mid.Pers. šudan, šaw- "to go;" Av. š(ii)auu-, šiyav- "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."

becquerel
  بکرل   
becquerel (#)

Fr.: becquerel   

The → SI unit of → radioactivity. One becquerel corresponds to the → disintegration of one atom per second. Abbreviation: Bq. → curie.

Named for the French physicist Henri Becquerel (1852-1908), who discovered radioactivity in 1896.

Bedin I
  بدین I   
Bedin I

Fr.: Bedin I   

A → dwarf spheroidal galaxy belonging to the → Local Group that was discovered serendipitously in 2019. Bedin I was detected using extremely deep → HST images (V ~ 30 mag) obtained for the purpose of investigating the → white dwarf cooling track of the Galactic → globular cluster NGC 6752. Bedin I is too faint and too close to the core of NGC 6752 for detection in earlier surveys. The discovery paper derives a → distance modulus of (m - M)0 = 29.70 ± 0.13 mag from the observed → red giant branch, i.e. ~ 8.7 → megaparsecs (~ 30 million → light-years), and a size of ~ 840 × 340 pc, about one-fifth the size of the → Large Magellanic Cloud. This object is most likely a relatively isolated → satellite galaxy of the nearby great → spiral galaxy NGC 6744. The study suggests the presence of an old (~ 13 Gyr) and → metal-poor ([Fe/H] ~ -1.3) population in Bedin I.

Named after the first author of the discovery paper, L. R. Bedin et al., 2019, MNRAS 484, L54.

bedrock
  سنگ‌بستر   
sangbastar (#)

Fr.: socle   

Solid → rock present beneath any → soil, → sediment, or other surface cover. In some locations it may be exposed at earth's surface.

Bedrock, from bed (O.E. bed, from P.Gmc. *badjam "sleeping place dug in the ground;" PIE *bhedh- "to dig, pierce") + → rock.

Sangbastar, from sang "stone, rock," → stone, + bastar "bed" (Mid.Pers. vistarak, cognate with Mod.Pers. gostar "a bed; spreading; scatterer," Av. star-, starəta- "spread," from star- "to spread," Skt. strnâti).

<< < -es -iv -ti 217 a- abe abs abs acc acc ach act act ada adi adv aff agg Alc Alf ali all alp alt Ama amp ana ang ang ann ano ant ant ape apo app aps arc arg arm art ass ast ast ast atm ato att aur aut axi B-t bai Bal bar bar Be bee Bes bi- bif bin bin bio bis bla bli blu Boe Bol bor bou bra bri Bro bum CAI cal Can cap car car cat cat CCD Cel cen CGS cha cha che che 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 coo cor cor cor cos cos cos cou cov cra cri cro cry cum cur cyc d'A dar dat DC dea dec dec dec def def deh Del den dep des det dev dia dif dif dif dim dip dir dis dis dis dis dis div dom dou dou dri dup dus dyn dyn ear eas ecl Edd eff Ein Ekm ele ele ele ele ell emb emi enc ene ent eph equ equ equ eru eth eup eve EX exc exe exi exo exp ext ext ext fac fal far fec Fer fer fie fin fir fis fla flo flu fog for for Fou fra fre Fre Fro fus G-t gal gal Gam gas Gau Gem gen geo geo geo gia gla gol gra gra gra gra Gre Gre gui H a haf Hal har har He- hea hel Hel her Her hie hig his hom hor hot Hub Hug hur hyd hyd hyl hyp ice ide ima imp imp imp inc ind ind ine inf inf Inf inj InS ins int int int int int int int int inv inv ion iro Isl iso iso Jac jet jud jur Kel Kep kil kly L d Lag lam Lap lar lat law Lea len lep lib lig lin lin lin liq lit loc log lon Los low lum lun Lut Lyr mac mag mag mag mag mag maj man Mar mas mas mat mea mec mem mer mes met met met mic mid mil min Mir Miz mod mol mon moo MOS mul mul mut nai nas nat neb neg Neu neu New New Nih noi non non non nor nuc nuc nul nut obj obl obs occ oct off old one ope opp opt opt orb ord org Ori osc oth ove oxi pac Pal par par Par par pas Pau Pel per per per per per per pha phi pho pho pho phy pip Pla pla pla pla pla Plu Poi pol pol pol pop pos pos pot Pra pre pre pre Pri pri pri pro pro pro pro pro pro pro Pto pul puz qua qua qua qua qui rad rad rad rad rad rad rai ran Ras Ray rea rec rec rec red red ref reg reg rel rel rel rep res res res res rev rhe Rie Rig Rit roe Ros rot Ruf Ryd Sag sam sat sca sca Sch Sco sec sec sec seg sel sem sen set sha SHB sho sib sie sil sim sin sit sky slo sno sod sol sol sol sol sor sou Spa spa spe spe spe sph spi Spi spr sta sta sta sta sta ste ste Ste sto str str sub sub sub suf sun sup sup sup sup sur swo syn sys tak Tay Tel ten ter tet the the the thi Tho thu tid tim toa top tot tra tra tra tra tri tri tro Tru tur twi Typ UBV ult unb uni uni uni up ura uti val var vec Vel ver ver vig vir vis VLT vol wad was wav wav wea wei Whe Wie win WN5 Wol X-r yea You zer zod > >>