An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



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Number of Results: 403
Godunov method
  روش ِ گودونوف   
raveš-e Godunov

Fr.: méthode de Godunov   

In numerical analysis and fluid dynamics, a conservative scheme for solving → partial differential equations based on utilizing the solution of the local → Riemann problem at each time step.

Suggested by Sergei K. Godunov (1929-) in 1959, Math. Sbornik, 47, 271, translated 1969, US Joint Publ. Res. Service, JPRS 7226; → method.

  تلا، طلا، زر   
talâ (#), zarr (#)

Fr.: or   

A yellow, ductile → metal which occurs naturally in veins and alluvial deposits associated with quartz or pyrite; symbol Au (L. aurum "shining dawn"). → Atomic number 79; → atomic weight 196.9665; → melting point 1,064.43 °C; → boiling point 2,808 °C; → specific gravity 19.32 at 20 °C.

M.E., from O.E. gold, from P.Gmc. *gulth- (cf. O.H.G. gold, Ger. Gold, Du. goud, Dan. guld, Goth. gulþ), from PIE base *ghel-/*ghol- "yellow, green;" cf. Mod.Pers. zarr "gold," see below.

Talâ "gold," variants tala, tali.
Zarr "gold;" Mid.Pers. zarr; Av. zaranya-, zarənu- "gold;" O.Pers. daraniya- "gold;" cf. Skt. hiranya- "gold;" also Av. zaray-, zairi- "yellow, green;" Mod.Pers. zard "yellow;" Skt. hari- "yellow, green;" Gk. khloe literally "young green shoot;" L. helvus "yellowish, bay;" Rus. zeltyj "yellow;" P.Gmc. *gelwaz; Du. geel; Ger. gelb; E. yellow.

Goldbach's conjecture
  هاشن ِ گلدباخ   
hâšan-e Goldbach

Fr.: conjecture de Goldbach   

Every number greater than 2 is the sum of two → prime numbers. Goldbach's number remains one of the most famous unsolved mathematical problems of today.

Named after the German mathematician Christian Goldbach (1690-1764); → conjecture.

golden number
  عدد ِ زرّین   
adad-e zarrin (#)

Fr.: nombre d'or   

1) The number giving the position of any year in the lunar or → Metonic cycle of about 19 years. Each year has a golden number between 1 and 19. It is found by adding 1 to the given year and dividing by 19; the remainder in the division is the golden number. If there is no remainder the golden number is 19 (e.g., the golden number of 2007 is 13).
2) Same as → golden ratio.

Golden, adj. of → gold; → number.

golden ratio
  وابر ِ زرین   
vâbar-e zarrin

Fr.: nombre d'or   

If a line segment is divided into a larger subsegment (a) and a smaller subsegment (b), when the larger subsegment is related to the smaller exactly as the whole segment is related to the larger segment, i.e. a/b = (a + b)/a. The golden ratio, a/b is usually represented by the Greek letter φ. It is also known as the divine ratio, the golden mean, the → golden number, and the golden section. Its numerical value, given by the positive solution of the equation φ2 - φ - 1 = 0, is approximately 1.618033989. The golden ratio is closely related to the → Fibonacci sequence.

golden; → ratio.

gossamer ring
  حلقه‌ی ِ تنته   
halqe-ye tanté

Fr.: anneau ténu   

An extremely faint and broad ring (in fact two rings) of tiny particles around → Jupiter lying just outside the main ring.

Gossamer "a film of cobwebs floating in air in calm clear weather; an extremely delicate variety of gauze, used esp. for veils," from M.E. gossomer, from gos "goose" + somer "summer." Possibly first used as name for late, mild autumn, a time when goose was a favorite dish, then transferred to the cobwebs frequent at that time of year; → ring.

Halqé, → ring; tanté "cobweb, spider's web," from tanidan "to spin, twist, weave" (Mid.Pers. tanitan; Av. tan- to stretch, extend;" cf. Skt. tan- to spin, stretch;" tanoti "stretches," tantram "loom;" Gk. teinein "to stretch, pull tight;" L. tendere "to stretch;" PIE base *ten- "to stretch"), Pers. târ "string," tur "fishing net, net, snare," and tâl "thread" (Borujerdi dialect) belong to this family; variants tanta "cobweb," tanadu, tafen, kartané, kârtané, kâtené, Pashtu tanistah "cobweb;" cf. Skt. tantu- "cobweb, thread, string."

Gould's Belt
  کمربند ِ گولد   
kamarband-e Gould (#)

Fr.: ceinture de Gould   

A band of hot, young stars (O and B types) and molecular clouds that stretches around the sky. It is tilted by about 20 degrees with respect to the Galactic plane, and has a diameter of about 3000 light-years.

Named after the American astronomer Benjamin A. Gould (1824-1896), who discovered it in 1879 by studying the distribution of the nearest luminous stars in space; → belt.


Fr.: gouverner   

General: To rule over, to exercise authority.
Science: To serve as or constitute a law for, e.g. physical laws governing star formation, the Universe, and so on.
To regulate the speed of (an engine) with a governor.

From O.Fr. governer "to govern," from L. gubernare "to direct, rule, guide," originally "to steer," from Gk. kybernan "to steer or pilot a ship" (the root of cybernetics).

Faršâyidan, from Av. fraxšā(y)- "to establish authority, to deploy lordship," from fra- "forward, forth" (Av. pouruua- "first"; cf. Skt. pūrva- "first," pra- "before, formerly," Gk. pro; L. pro; O.E. fyrst "foremost," superlative of fore, from P.Gmc. *furisto; E. fore) + xšā(y)- "to rule, have power," xšayati "has power, rules," xšāyô "power;" O.Pers. xša- "to rule," pati-xša- "to have lordship over," Xšyāršan- "hero among kings" or "ruling over heroes" the proper name of the Achaemenid emperor Hellenized as Xerxes, upari.xšay- "to rule over," xšāyaθiya- "king;" Mid.Pers. šâh "king," pâdixšâ(y) "ruler; powerful; authoritative;" Mod.Pers. šâh "king," pâdšâh "protecting lord, emperor, monarch, king," šâyestan "to be worth, suit, fit;" cf. Skt. ksā- "to rule, have power," ksáyati "possesses;" Gk. ktaomai "I acquire," ktema "piece of property;" PIE base *tkeh- "to own, obtain."


Fr.: régulateur   

A regulating device for maintaining uniform speed regardless of changes of load, as by controlling the supply of gas, steam, fuel, etc.

Agent noun from → govern.

foruzamin (#)

Fr.: graben   

A block of the Earth's crust, bounded by two normal faults, that has dropped downward in relation to adjacent portions.

Graben, from Ger. Graben "ditch, trench;" O.H.G. graban "ditch," grab "grave, tomb;" Goth. graban "ditch;" P.Gmc. *graban; cf. O.E. græf "grave, ditch;" E. a grave; PIE base *ghrebh-/*ghrobh- "to dig, to scratch, to scrape."

Foruzamin, from foru- + zamin. The first component foru- "down, downward; below; beneath;" Mid.Pers. frôt "down, downward;" O.Pers. fravata "forward, downward;" cf. Skt. pravát- "a sloping path, the slope of a mountain." The second component 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."

  ۱) پداک؛ ۲) پداکیدن   
1) padâk; 2) padâkidan

Fr.: 1) grade, échelon; 2) classer, noter, graduer   

1) A degree or step in a scale, as of rank, advancement, quality, value, or intensity.
2) To arrange in a series of grades; class; sort (

From Fr. grade "grade, degree," from L. gradus "step, pace, gait, walk;" figuratively "a step, stage, degree," related to gradi "to walk, step, go," and second element in congress, progress, etc.; from PIE *ghredh-; cf. Lith. gridiju "to go, wander," O.C.S. gredo "to come," O.Ir. in-greinn "he pursues."

Padâk, from Baluci padâk "step, stair, ladder" (ultimately from Proto-Ir. *padaka-), older form of Pers. pâyé "step, base," from Mid.Pers. pâd, pây; Av. pad-, cf. Skt. pat: Gk. pos, genitive podos; L. pes; PIE *pod-/*ped-.

ziné (#)

Fr.: gradient   

1) General: Degree of slope.
2) Physics: Change in the value of a quantity (as temperature, pressure) with change in a given variable.
3) Math.: A differential → operator (symbol → nabla, ∇) that, operating upon a function (f) of several variables, creates a → vector whose coordinates are the → partial derivatives of the function: ∇f = (∂f/∂x)i + (∂f/∂y)j + (∂f/∂z)k. The gradient of a → scalar function is a vector function.

From L. gradient-, gradiens, pr.p. of gradi "to walk, go," from grad- "walk" + -i- thematic vowel + -ent suffix of conjugation.

Ziné "ladder, steps, stair," may be related to ciné, from cidan "to place (something) above/upon (another similar thing);" cf. Lori râ-zina, Yazdi râ-cina "stairs," Nâyini orcen "stairs, ladder;" the phoneme change -c- into -z-, as in gozidan, gozin-/cidan, cin- both deriving from Proto-Ir. *cai- "to heap up, gather, collect."

  پداکوار، پای‌پایه   
padâkvâr, pâypâyé

Fr.: graduel   

Proceeding, taking place, changing by small degrees.

From M.L. gradualis, from L. gradus "step."

Padâkvâr, from padâk "grade," + -vâr a suffix which denotes "suiting, befitting, resembling, in the manner of, possession."
Pâypâyé "step by step," from pây, pâ "foot, step," → foot.

gradual burst
  بلک ِ پداکوار، ~ پای‌پایه   
belk-e padâkvâr, ~ pâypâyé

Fr.: sursaut graduel   

A burst that happens gradually, in contrast to a sudden burst.

gradual; → burst.

  ۱) پداک دادن، پداکیدن؛ ۲) پداک گرفتن، پداکیده شدن؛ ۳) پداک دادن، پداکیدن؛ ۴) پداکمند، پداکیده   
1) padâk dâdan, padâkidan; 2) padâk gereftan, padâkidé šodan; 3) padâk dâdan, padâkidan; 4) padâkmand, padâkidé

Fr.: 1) graduer; 2) obtenir son diplôme; 3) conférer un diplôme; 4) licencié, diplômé   

1) To divide into or mark with degrees or other divisions, as the scale of a thermometer.
2) To receive a degree or diploma on completing a course of study (often followed by from).
3) To confer a degree upon, or to grant a diploma to, at the close of a course of study, as in a university, college, or school.
4) A person who has received a degree or diploma on completing a course of study, as in a university, college, or school (

M.E., from M.L. graduatus, of graduari "to take a degree," from L. gradus "step, → grade."

1, 3) Padâk dâdan, compound infinitive, padâkidan simple infinitive, both from padâk, → grade, + dâdan "to give, grant," → datum, and -idan, → -fy.
2) Padâk gereftan, from padâk + gereftan "→ take, hold."
4) Padâkmand, from padâk + -mand suffix of possession and ability, → -al; padâkidé, p.p. of padâkidan, as above.

  پداکش، پداک‌دهی، پداک‌گیری   
padâkeš, padâk dehi, padâk giri

Fr.: graduation   

1) Marking the scale of an instrument, e.g. the stem of a thermometer is graduated in degrees.
2) An act of graduating; the state of being graduated.

Verbal noun of → graduate.

dâné (#)

Fr.: grain   

1) A small, hard seed of plants, especially the seed of cereals.
2) A tiny portion or particle of something such as sand or salt; → dust grain.

M.E. grain, grein, from O.Fr. grein, from L. granum "seed;" akin to corn.

Dâné "grain, seed;" Mid.Pers. dân, dânag "seed, corn;" Av. dānô- in dānô.karš- "carrying grains; an ant;" cf. Skt. dhânâ- "corn, grain;" Tokharian B tāno "grain;" Lith. duona "corn, bread."

grain coagulation
  ماسش ِ دانه   
mâseš-e dâné

Fr.: coagulation des grains   

Sticking together of micron- to centimetre-sized grains occurring in the interstellar and protoplanetary environments to form larger grain agglomerates.

grain; → coagulation.

grain evaporation
  بخارش ِ دانه   
boxâreš-e dâné

Fr.: évaporation des grains   

Conversion of dust grains into smaller grains due to high environmental temperatures.

grain; → evaporation.

grain formation
  دیسش ِ دانه   
diseš-e dâné

Fr.: formation des grains   

The process by which dust grains are assembled or produced.

grain; → formation.

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