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 cro cru cub cur cyc Cyn dar dat day de- dec dec dec def def deg del den dep Des det deu dex die dif dif dil dip dir dis dis dis dis dis div dom Dor dou Dra duc dus dwa dyn e-t ear ecl eco eff Ein Ein ele ele ele ele ele elv emi emp ene enr epa epo equ equ Err Eta Eul eva evo exc exc exh exo exp exp ext ext Fab fai fan fau fel fer fic fil fin fir fla fli flu foc for for for fra fre fre fro fun fuz Gal gal gal Gar gau geg gen geo geo geo ger gla gly gra gra gra gra gra Gre gro GYR Had Hal hap Har HD hea hel hel hep Her hex hig Him hol hor hos hov Hub Hun hyd hyd hyd hyp IC ide ill Ima imp imp inc inc ind ine inf inf inf ini inp ins ins int int int int Int int int int inv ion Iri irr iso iso ite jel Jou JUp Kan Kep Kil kin 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 mar mas mas mat max mea mec meg men mer met met Met mic mid Mil min Mir mix mod mod mol mon mor mov mul mur n-b nan nat nea neg Ner neu new New NGC noc nom non non nor nou nuc nuc num O-p obl obs obs oce Of? ohm omn opa Oph opt opt or orb ord Ori ort osc out ove ozo pal pan par par par par pat pec pen per per per per per Pfu pha pho pho pho phy pie pla Pla pla pla pla plu poi pol pol pol pol por pos pot pow pre pre pre pre pri pri pri pro pro pro pro Pro pro Prz pul pum Pyx qua qua qua qua R A rad rad rad rad rad rad Ram Ran rat rea rea rec rec red red ref ref reg rei rel rel rem rep res res res ret rev rhy rif Rin rob Rom rot rot rum S s Sak San sav sca Sch Sch scr sec sec SED sei sel sem seq sex Sha she sho sid sig sil sim sin siz sla Sma SNR Sof sol sol sol sol sou sou spa spe spe spe spe sph spi spo squ sta sta sta sta ste ste ste sto sto str str sub sub sub sum sup sup sup sup sur sus sym syn syz tan tea tem ten ter the the the the thi thr tid til tip tom tor tou tra tra tra tra Tri tri tru tsu tur two Typ ult umb unc uni uni unk upp urg uvb val var Veg vel ver vib vio vir vis Voi vow wan wat wav WC wea wel whi Wil wir WNh wor X-r Yer Z s zer [C > >>

Number of Results: 12942 Search : far
Greenwich Mean Sidereal Time (GMST)
  زمان ِ اختری ِ میانگین ِ گرینویچ   
zamân-e axtari-ye miyângin-e Greenwich

Fr.: temps sidéral moyen de Greenwich   

The → sidereal time related to the angle between the → prime meridian and the → mean vernal equinox, measured in the plane of the equator.

mean; → Greenwich Meridian; → sidereal; → time.

Greenwich Meridian
  نیمروزان ِ گرینویچ   
nimruzân-e Greenwich

Fr.: méridien de Greenwich   

The → prime meridian that separates east from west in the same way that the Equator separates north from south. It is defined by the position of the → Airy transit circle.

A borough in southeast London, England, on the Thames River. It is the site of the original Royal Observatory, through which passes the prime meridian, or longitude 0°; → meridian.

Greenwich sidereal date
  روز ِ اختری ِ گرینویچ   
ruz-e axtari-ye Greenwich

Fr.: jour sidéeal de Greenwich   

The number and fraction of → mean sidereal days elapsed on the → Greenwich meridian since 12h January 1, 4773 BC (mean sidereal).

Greenwich meridian; → sidereal; → date.

Greenwich sidereal day number
  شماره‌ی ِ روز ِ اختری ِ گرینویچ   
šomâre-ye ruz-e axtari-ye Greenwich

Fr.: nombre du jour sidéral de Greenwich   

The integral part of the → Greenwich sidereal date.

Greenwich; → sidereal; → day; → number.

Gregorian calendar
  گاهشمار ِ گرگوری   
gâhšomâr-e Gregori (#)

Fr.: calendrier grégorien   

A → solar calendar in which the year length is assumed to be 365.2425 solar days. It is now used as the civil calendar in most countries. The Gregorian calendar is a revision of the → Julian calendar instituted in a papal bull by Pope Gregory XIII in 1582. The reason for the calendar change was to correct for drift in the dates of significant religious observations (primarily Easter) and to prevent further drift in the dates.

Named after Pope Gregory XIII (1502-1585), an Italian, born Ugo Boncompagni, Pope from 1572 to 1585, who ordered the reform of the Julian calendar; → calendar.

Gregorian telescope
  دوربین ِ گرگوری، تلسکوپ ِ ~   
durbin-e Gregori, teleskop-e ~ (#)

Fr.: télescope de Gregory   

A reflecting telescope in which the light rays are reflected from the primary mirror to a concave secondary mirror, from which the light is reflected back to the primary mirror and through the central hole behind the primary mirror. Compare with the → Cassegrain telescope, in which the secondary mirror is convex.

Named after the Scottish mathematician and astronomer James Gregory (1638-1675), who devised the telescope, but did not succeed in constructing it; → telescope.

Greisen-Zatsepin-Kuzmin limit (GZK)
  حد ِ گریسن-زاتسپین-کوزمین   
hadd-e Greisen-Zatsepin-Kuzmin

Fr.: limite de Greisen-Zatsepin-Kuzmin   

A theoretical limit of approximately 6 × 1019  → electron-volts for the energy of → cosmic rays above which they would lose energy in their interaction with the → cosmic microwave radiation background photons. Cosmic ray protons with these energies produce → pions on blackbody photons via the Δ resonance according to: γCMB + p → p + π0, or γCMB + p → n + π+, thereby losing a large fraction of their energy. These interactions would reduce the energy of the cosmic rays to below the GZK limit. Due to this phenomenon, → Ultra-high-energy cosmic rays are absorbed within about 50 Mpc.

Named after Kenneth Greisen (1966), Physical Review Letters 16, 748 and Georgiy Zatsepin & Vadim Kuzmin (1966), Journal of Experimental and Theoretical Physics Letters 4, 78; → limit.

grid
  شباک   
šabâk (#)

Fr.: grille   

1) A → grating of crossed bars; gridiron.
2) A → network of → horizontal and → perpendicular lines, uniformly spaced, for locating points on a map, chart, or aerial photograph by means of a system of coordinates.
3) Electricity: i) A metallic framework employed in a storage cell or battery for conducting the electric current and supporting the active material.
ii) A system of electrical distribution serving a large area, especially by means of high-tension lines.

Shortening of gridiron "a utensil consisting of parallel metal bars on which to broil meat or other food," from M.E. griderne, from gridel, from O.Fr. gredil, gridil, from L. craticula "gridiron, small griddle," diminutive of cratis "wickerwork."

Šabâk, from Laki šowâk "a net woven from goat fleece used for carrying chaff or fruits like melon," variants šâvâk (Lori), šavak (Nahâvand).

grinding
  سابش   
sâbeš

Fr.: ébauchage   

A first step in making a telescope mirror, which consists of rubbing the glass blank with hard tools (glass, tile, or metal) and abrasive grit to produce a concave form. → figuring; → polishing.

Grinding, verbal noun of grind, from O.E. grindan, forgrindan "destroy by crushing," from P.Gmc. *grindanan (cf. Du. grenden), from PIE *ghrendh- "crushing" (cf. L. frendere "to crush, grind;" Gk. khondros "granule, groats").

Sâbeš, verbal noun of sâbidan, variants sâyidan, pasâvidan "to touch" (Khotanese sauy- "to rub;" Sogdian ps'w- "to touch;" Proto-Iranian *sau- "to rub").

gripe
  گله   
gelé (#)

Fr.: doléance   

A minor → complaint.

M.E. gripen, from O.E. gripan; cognate with Du. grijpen, Ger. griefen.

Gelé, → complain.

grism
  گریسم   
grism (#)

Fr.: grism   

An optical dispersing device used in a spectrograph. It is a combination of a prism and a grating, in the sense that the grating is placed side by side to one surface of a small-angle prism.

Grism, from gr(ating) + (pr)ism.

grit
  شن   
šen (#)

Fr.: grain abrasif   

Abrasive particles or granules, classified into predetermined sizes, typically of Silicon Carbide or Aluminum Oxide, used between the mirror and tile tool to grind the glass.

Grit, from O.E. greot "sand, dust, earth, gravel," from P.Gmc. *greutan "tiny particles of crushed rock" (cf. O.S. griot; O.N. grjot "rock, stone;" Ger. Grieß "grit, sand"); PIE base *ghreu- "to rub, pound, crush."

Šen "sand, grit."

groin
  کشال، کشاله   
kašâl (#), kašâlé (#)

Fr.: aine   

Anatomy: The depression on either side of the front of the body between the thigh and the abdomen.

M.E. grynde "groin," originally "depression in the ground," from O.E. grynde "abyss," perhaps also "depression, hollow," related to → ground.

Kašâl, kašâlé, literally "side, edge, margin," cf. Dari Kermâni kašâr, Kermâni kešâl "side, edge," from kašidan "to draw, pull, trace, trail," → galaxy.

groma
  گروما   
gromâ

Fr.: groma   

An instrument composed of a vertical staff and a horizontal cross with a plumb line at the end of each arm. It was used in ancient Roman empire to survey straight lines, squares, and rectangles.

From L. groma, gruma, from Gk. → gnomon, possibly through Etruscan.

groove
  شیار   
šiyâr (#)

Fr.: trait, sillon   

grating groove.

Groove, from O.N. grod "pit," or M.Du. groeve "furrow, ditch," from P.Gmc. *grobo (cf. O.H.G. gruoba "ditch," Goth. groba "pit, cave," O.E. græf "ditch"), related to grave (n.).

Šiyâr "furrow, ploughed ground," from Av. karši-, karša- "furrow," karšuiiā "plowed (land)," related to Mod.Pers. kašidan/kešidan "to carry, draw, protract, trail, drag;" Mid.Pers. kešidan "to draw, pull;" from Av. karš- "to draw; to plow;" cf. Skt. kars-, kársati "to pull, drag, plough," karṣū- "furrow, trench;" Gk. pelo, pelomai "to be in motion, to bustle;" PIE base kwels- "to plow."

ground
  ۱) زمین؛ ۲) زمینه   
1) zamin; 2) zaminé (#)

Fr.: sol, terrain   

1) The surface of the Earth; soil.
2) The foundation or basis on which a belief or action rests.

From O.E. grund "foundation, ground, surface of the earth," from P.Gmc. *grundus (cf. Du. grond, Ger. Grund "ground, soil, bottom").

1) Zamin, variant zami "earth, ground," from Mid.Pers. zamig "earth;" Av. zam- "the earth;" cf. Skt. ksam; Gk. khthôn, khamai "on the ground;" L. homo "earthly being" and humus "the earth" (as in homo sapiens or homicide, humble, humus, exhume); PIE root *dh(e)ghom "earth."
2) Zaminé, from zamin + nuance suffix .

ground state
  حالت ِ زمینه   
hâlat-e zaminé (#)

Fr.: état fondamental   

The lowest energy state of an atom, molecule, or ion, when all electrons are in their lowest possible energy levels, i.e. not excited.

ground; → state.

ground-based observation
  نپاهش از زمین   
nepâheš az zamin

Fr.: observation au sol   

An astronomical observation carried out using a telescope on Earth, as opposed to that from an orbiting satellite.

ground; based, adj. of base, from O.Fr. bas, from L. basis "foundation," from Gk. basis "step, pedestal," from bainein "to step;" → observation.

Nepâheš, → observation; az "from," → ex-; zamin, → ground.

group
  ۱) گروه؛ ۲) گروهاندن؛ گروهیدن   
1) goruh (#); 2) goruhândan; goruhidan

Fr.: 1) groupe; 2) grouper; se grouper   

1a) Any collection or assemblage of persons or things considered together or regarded as belonging together; e.g. → Local Group of galaxies.
1b) Math.: A set of elements a, b, c, ..., finite or infinite in number, with a rule for combining any two of them to form a "product," subject to the following four axioms: → closure axiom, → associative axiom, → identity axiom, and → inverse axiom.
2a) (v.tr.) To place or associate together in a group.
2b) (v.intr.) To be part of a group.

From Fr. groupe "cluster, group," from It. gruppo "cluster, packet, knot," likely from P.Gmc. *kruppa "round mass, lump."

Goruh "group," from Mid.Pers. grôh "group, crowd."

group theory
  نگره‌ی ِ گروه   
negare-ye goruh (#)

Fr.: théorie des groupes   

A branch of mathematics concerned with structures called → groups and the description of their properties. Group theory provides a powerful formal method of analyzing abstract and physical systems in which → symmetry is present. It has a very considerable use in physics, especially → quantum mechanics, notably in analyzing the → eigenstates of energy of a physical system.

group; → theory.

<< < -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 cro cru cub cur cyc Cyn dar dat day de- dec dec dec def def deg del den dep Des det deu dex die dif dif dil dip dir dis dis dis dis dis div dom Dor dou Dra duc dus dwa dyn e-t ear ecl eco eff Ein Ein ele ele ele ele ele elv emi emp ene enr epa epo equ equ Err Eta Eul eva evo exc exc exh exo exp exp ext ext Fab fai fan fau fel fer fic fil fin fir fla fli flu foc for for for fra fre fre fro fun fuz Gal gal gal Gar gau geg gen geo geo geo ger gla gly gra gra gra gra gra Gre gro GYR Had Hal hap Har HD hea hel hel hep Her hex hig Him hol hor hos hov Hub Hun hyd hyd hyd hyp IC ide ill Ima imp imp inc inc ind ine inf inf inf ini inp ins ins int int int int Int int int int inv ion Iri irr iso iso ite jel Jou JUp Kan Kep Kil kin 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 mar mas mas mat max mea mec meg men mer met met Met mic mid Mil min Mir mix mod mod mol mon mor mov mul mur n-b nan nat nea neg Ner neu new New NGC noc nom non non nor nou nuc nuc num O-p obl obs obs oce Of? ohm omn opa Oph opt opt or orb ord Ori ort osc out ove ozo pal pan par par par par pat pec pen per per per per per Pfu pha pho pho pho phy pie pla Pla pla pla pla plu poi pol pol pol pol por pos pot pow pre pre pre pre pri pri pri pro pro pro pro Pro pro Prz pul pum Pyx qua qua qua qua R A rad rad rad rad rad rad Ram Ran rat rea rea rec rec red red ref ref reg rei rel rel rem rep res res res ret rev rhy rif Rin rob Rom rot rot rum S s Sak San sav sca Sch Sch scr sec sec SED sei sel sem seq sex Sha she sho sid sig sil sim sin siz sla Sma SNR Sof sol sol sol sol sou sou spa spe spe spe spe sph spi spo squ sta sta sta sta ste ste ste sto sto str str sub sub sub sum sup sup sup sup sur sus sym syn syz tan tea tem ten ter the the the the thi thr tid til tip tom tor tou tra tra tra tra Tri tri tru tsu tur two Typ ult umb unc uni uni unk upp urg uvb val var Veg vel ver vib vio vir vis Voi vow wan wat wav WC wea wel whi Wil wir WNh wor X-r Yer Z s zer [C > >>