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
downsizing
  بزرگ-به-کوچک   
bozorg-bé-kucak

Fr.:   

A scenario of galaxy formation whereby massive galaxies formed earlier in the history of the → Universe (i.e. at high → redshifts) and completed their → star formation process more rapidly than low-mass galaxies. This scenario contrasts with what might be expected from simple → hierarchical structure formation scenarios, which predict that large galaxies formed in more recent times through the → merging of small galaxies.

Downsizing, first suggested by Cowie et al. (1996, AJ 112, 839), from downsize (v.), is a new sense for this term. Its current main meaning in non astrophysical contexts is "to make in a smaller size, or become smaller in size (in particular in economic vocabulary, by reductions in personnel)," from → down + → size.

Bozorg-bé-kucak, literally "large to small," from bozorg, → large, + "to" + kucak, → small.

downstream
  فروداب   
forudâb (#)

Fr.: en aval   

1) With or in the direction of the current of a stream. → upstream.
2) Of or pertaining to the latter part of a process or system.

down; → stream.

Forud, → incidence; water, → water.

DQ white dwarf
  سفید‌کوتوله‌ی ِ DQ   
sefid kutule-ye DQ

Fr.: naine blanche DQ   

A → white dwarf whose spectrum shows carbon features of any kind.

D short for → dwarf; Q a convention; → white.

Draco
  اژدها   
eždahâ (#)

Fr.: Dragon   

The Dragon. A large constellation that winds around the north → celestial pole, appearing to encircle → Ursa Minor. The north → ecliptic pole also lies within Draco. Abbreviation: Dra, genitive form: Draconis.

O.Fr. dragon, from L. draco "serpent, dragon," from Gk. drakon "serpent, seafish," from drak-, strong aorist stem of derkesthai "to see clearly," perhaps literally "the one with the (deadly) glance," cf. Av. darəs- "to look," huuarə.darəsa- "having the appearance of the sun," Skt. darś- "to see, appear, look, show," dárśya- "worthy of being seen;" PIE base *derk- "to look."

Eždahâ, from Mid.Pers. aždahâg, ažidahâk, from Av. aži.dahāka- "the name of an evil king in the Iranian mythology," from aži- "serpent; dragon, monster" (Mid.Pers. až, âž, aži), cf. Skt. áhi- "snake, adder," Gk. ékhis, óphis "snake," L. anguis "snake," Arm. auj, Russ. , Lith. angis; PIE base *angw(h)i- "snake, worm." The etymology of the second component, Av. dahāka-, is a matter of discussion. It is probably related to dahaka- "stinging, tormenting," from dah- "to sting, to do harm."

Draco Dwarf
  کوتوله‌ی ِ اژدها   
kutule-ye eždahâ

Fr.: Naine du Dragon   

A dwarf elliptical galaxy that is a satellite of our Galaxy and lies at a distance of about 250,000 light-years from the Galactic center. Its diameter is only about 3,500 light-years, and its absolute magnitude -8.6, making it the least luminous galaxy known.

Draco; → dwarf.

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

Fr.: mois draconitique   

The time interval between two successive passages of the Moon through its → ascending node, 27.212 220 days (27d 5h 5 m 35.8s). Draconic month is important for predicting → eclipses. Also called draconitic month, nodical month.

Draconic, adj. of dragon, → Draco, referring to a mythological dragon for the following reason. Since an eclipse occurs when the Earth, the Sun, and a node are aligned and moreover the Moon is situated near the node, it was believed that a dragon that resided in the node swallowed the Sun or the Moon. → month.

Mâh, → month.
Gowzahri, related to gowzahr, from Mid.Pers. gowzihr "a node of the lunar orbit" [gowzihr sar ("head") = ascending node, gowzihr dumb ("tail") = descending node], also the astrological dragon, from Av. gao-ciθra- "keeping in it the seed of the ox," epithet of the Moon, since according to Iranian mythology the Moon keeps the seed/sperm of bovine animals; from gao- "cow, ox, bull" (Mod.Pers. gâv, Skt. gaus-, Gk. bous "ox," Arm. kov, O.E. cu, PIE *gwou-) + ciθra- "origin, seed, lineage" (Mod.Pers. cehr "origin"). Gowzahr was loaned into Arabic astronomical texts as jawzahr.
Gerehi, adj. of gerehnode.

Draconids
  اژدهاییان   
eždahâiyân

Fr.: Draconides   

Two meteor showers with radiants in the constellation → Draco. One appears early in October and the other late in June.

Draconids, from → Draco constellation + → -ids suffix denoting "descendant of, belonging to the family of."

Eždahâyiyân, from eždahâ, → Draco, + -iyân-ids.

drag
  ۱) کره، ۲) وارانه؛ ۳) کریدن، کراندن   
1) kerré, 2) vârâné; 3) kerridan, kerrandan

Fr.: 1) traînée, entraînement; 2) traînée; 3) traîner   

1) General: The act of dragging or the state of being dragged.
2) Fluid mechanics: The → force that opposes the relative motion of an object through a → fluid. In → aeronautics, the component of aerodynamic force parallel to the relative wind tending to reduce the forward motion of the airplane. See also → lift; → thrust.
3) To pull or be pulled with force, especially along the ground or other surface.

From O.N. draga, O.E. dragan "to draw," from P.Gmc. *dragan "to draw, pull," from PIE base *dhragh- "to draw, drag on the ground" (cf. Skt. dhrajati "pulls, slides in," L. trahere "to pull," Rus. drogi "wagon."

Kerr, kerré, kerridan "drag," cf. Laki keronen, Hamadâni kerândan "to pull along, drag," Tâleši kernye, Tabari kərəš "to drag;" Lori, Hamadâni kerr "line, scratch;" related to Mid/Mod.Pers. kešidan, kašidan "to draw, protract, trail, drag, carry;" kâštan, keštan, kâridan "to cultivate, to plant, to make furrows;" Av. kar- "to strew seed, cultivate," kāraiieiti "cultivates," karš- "to draw (a furrow), till, plant;" cf. Skt. kar- "to scatter, strew, pour out," kars-, kársati "to pull, drag, plow;" Gk. pelo, pelomai "to move, to bustle;" PIE base kwels- "to plow."
Vârâné, from vâ-, opposition prefix, → de-, + râné, from rândan "to push, drive, cause to go" (causative of raftan "to go, walk, proceed," present tense stem row-, Mid.Pers. raftan, raw-, Proto-Iranian *rab/f- "to go; to attack").

Draine field
  میدان ِ درین   
meydân-e Draine

Fr.: champ de Draine   

A unit used to express the strength of → far ultraviolet (FUV) average → interstellar radiation field. It is equal to ~ 1.7 → Habing field.

Named after B. T. Draine, 1978, ApJS 36, 595.

Drake equation
  هموگش ِ دریک   
hamugeš-e Drake

Fr.: équation de Drake   

A probabilistic argument used to estimate the number of → intelligent, communicating → extraterrestrial civilizations in the → Milky Way galaxy. The Drake equation is:
N = R* . fp . ne . fl . fi . fc . L, where:
N = the number of → civilizations in our Galaxy with which → communication might be possible,
R* = the average rate of → star formation in our Galaxy,
fp = the fraction of those stars that have → planets,
ne = the average number of planets that can potentially support → life per star that has planets,
fl = the fraction of planets that could develop life at some point,
fi = the fraction of planets with life that actually go on to develop intelligent life,
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space,
L = the length of time for which such civilizations release detectable signals into space.
The first three terms of the equation have been successfully investigated by astronomers and are to some extent known. In contrast, values for the last four are very speculative. Drake himself estimates that N might be as high as 10,000. Carl Sagan was more optimistic, and came up with the value of a million or more for N. These estimates may be too optimistic. A pessimistic choice of parameters leads to N smaller than 1, which means that we might be the only technically sophisticated civilization in the Galaxy.

Frank Donald Drake (1930-); → equation.

dredge-up
  برونکشید   
borunkašid

Fr.: dragage, remontée   

A process by which the nucleosynthesis products inside a star are drawn to upper layers of the star. → first dredge-up; → second dredge-up; → third dredge-up.

From M.E. (Scots) dreg-, O.E. draeg- (in drægnet "dragnet"), akin to dragan "to draw" + up.

Birunkašid, past stem of birun kašidan, from birun "out, the outside" (Mid.Pers. bêron, from "outside, out, away" + rôn "side, direction," Av. ravan- "(course of a) river") + kašidan "to draw," Mid.Pers. kašitan, Av. karš- "to draw," Skt. kars-, kársati "to pull, drag, plough," Gk. pelo, pelomai "to be busy, to bustle."

Dresden codex
  نبیگان ِ درسدن   
nebigân-e Dresden (#)

Fr.: codex de Dresden   

A pre-Colombian Maya manuscript consisting of numerous calendar and astronomical data, probably dating from the 12th century. It seems that it is an updated copy of a document from the period of the old Maya Empire (4th-9th centuries). It contains a table which covers over 32 years, grouping 45 successive → lunations, divided into 69 groups of 5 or 6 lunations. The data are calculated in days and correspond remarkably to the intervals in an eclipse table: each group ends at the probable date of a solar eclipse (M.S.: SDE).

Dresden refers to the Dresden Library where the original document is preserved. It was bought in 1739 by the library director, Johann Christian Götze, who found it in a private library in Vienna. Its earlier history is unknown; codex, from L. codex earlier caudex "book, book of laws," literally "tree-trunk, book (formed originally from wooden tablets);" → codex.

drift
  ۱) دلک؛ ۲) دلکیدن   
1) delek; 2) delekidan

Fr.: 1) dérive; 2) dériver   

1a) General: A driving movement or force; impulse; impetus; pressure.
1b) Physics: A slight change of a quantity with time, for example the sensitivity of an electronic detector continuously operated during a long period as an effect of continued use.
1c) A slow change in frequency of a radio transmitter.
1d) Aerospace: The gradual deviation of a rocket or guided missile from its intended trajectory.
2) (v.intr.) To be carried along by currents of water or air, or by the force of circumstances.

From M.E. drift, from O.E. drifan "to drive," or from O.N. or M.Du. drift, from P.Gmc. *driftiz, related to *dribanan "to drive."

Delek from Lori, Laki, Hamadâni, Malâyeri "push, shove, drive;" variants Gilaki duko, Tâleši dako, Baluchi dhakkk(a) "push, shove, blow," Choresmian dh- "to hit," Kurd. dân/di- "to beat, hit," Proto-Iranian *daH- "to beat, hit, strike" (Cheung 2007); PIE base *dhen- "to hit, push;" delekidan, verb from delek.

drift curve
  خم ِ دلک   
xam-e delek

Fr.: courbe de passage   

In radio astronomy, the output response as a function of position for a given filter as the source passes through the beam.

drift; → curve.

drift rate
  نرخ ِ دلک   
nerx-e delek

Fr.: taux de dérive   

The amount of drift, in any of its several senses, per unit time.

drift; → rate.

drift velocity
  تندای ِ دلک   
tond-ye delek

Fr.: vitesse de dérive   

The average velocity of a charged particle in a plasma in response to an applied electric field.

drift; → velocity.

drive
  ۱) راندن؛ ۲) رانش، رانه   
1) rândan (#); 2) râneš (#), râné (#)

Fr.: 1) entraîner; 2) entraînement   

1a) To cause to move, to force to act. → continuum-driven wind, → dust-driven wind, → line-driven wind, → radiation-driven implosion, → radiation-driven mass loss, → radiation-driven wind.
1b) To cause and → guide the → motion of a → telescope.
2a) The act of driving.
2b) The → mechanism that imparts or transfers → power to a telescope so that it can move. → alpha drive, → delta drive, → drive accuracy, → slewing drive .

M.E. driven; O.E. drifan; cf. O.N. drifa, Goth. dreiban.

Rândan "to cause to go," causative of raftan "to go, walk, proceed" (present tense stem row-, Mid.Pers. raftan, raw-, Proto-Iranian *rab/f- "to go; to attack").

drive accuracy
  رشمندی ِ رانه   
rašmandi-ye râné

Fr.: précision de guidage   

The accuracy with which a telescope is moved by alpha or delta drives.

drive; → accuracy.

drizzle
  نرمه باران   
narmé bârân (#)

Fr.: bruine, crachin   

Very small, numerous, and uniformly distributed water drops that may appear to float while following air currents. Unlike fog droplets, drizzle falls to the ground.

Drizzle, dryseling "a falling of dew," from M.E. drysning, related to dreosan "to fall," cf. O.S. driosan, Goth. driusan.

Narmé bârân literally "smooth rain," from narmé, from narm "soft; smooth; mild," Mid.Pers. narm + bârân, → rain.

drop
  ۱) چکه؛ ۲) چکیدن   
1) cekké; 2) cekidan

Fr.: 1) goutte; 2) tomber goutte à goutte   

1a) A small quantity of liquid that falls or forms in a round or pear-shaped mass.
1b) A very small quantity of liquid; a very small quantity of anything.
2) To fall in small portions, as water or other liquid.

M.E. drop(e), from O.E. dropian; related to O.H.G. triofan, Du. drop, Ger. Tropfen.

Cekké, cekidan "drop; small, minute," cekidan "to drop."

<< < -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 > >>