An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



<< < -sc 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 SS sta sta sta sta ste ste ste Sto str str stu sub sub suc sun sup sup sup sup sur swa syn syn > >>

Number of Results: 1353
secular stability
  پایداری ِ دیریاز   
pâydâri-ye diryâz

Fr.: stabilité séculaire   

1) The condition in which the equilibrium configuration of a system is stable over long periods of time.
2) The condition of a star when it is stable against arbitrary adiabatic perturbations.

secular; → stability.

secular term
  ترم ِ دیریاز   
tarm-e diryâz

Fr.: terme séculaire   

In perturbation theory used in celestial mechanics, a steadily increasing disturbance. → periodic term.

secular; → term.

secular variation
  ورتش ِ دیریاز   
varteš-e diryâz

Fr.: variation séculaire   

Same as → secular perturbation.

secular; → variation.


Fr.: laïcité   

The view that religious considerations should be excluded from civil affairs or public education.



Fr.: laïcisation   

The process of organizing society or aspects of social life around non-religious values or principles.

Verbal noun of secularize "giyânidan" (گیانیدن); → secular

  ۱) زیله؛ ۲) زیلیدن   
1) zilé; 2) zilidan

Fr.: 1) sécurisé, en sécurité, sûr; 2) obtenir, fixer, attacher   

1) Free from or not exposed to danger or harm; safe.
2) To get hold or possession of; procure; obtain.

From L. securus "free from care, quiet, easy," also "careless, reckless;" of things, "free from danger, safe," from *se cura, from se "without, free from," + cura, → care.

Zilé, from Tabari zil, zilé "firm, fixed," zil hâkerdan "to fix, fasten," of unknown origin.


Fr.: sécurité   

1) Freedom from care, anxiety, or doubt; well-founded confidence.
2) Something that secures or makes safe; protection; defense.
3) A department or organization responsible for protection or safety (

secure; → -ity.

SED fitting
  سزکرد با SED   
sazkard bâ SED

Fr.: ajustement par distribution de l'énergie spectrale   

A technique that uses → spectral energy distribution results from models to reproduce observational data.

spectral energy distribution; → fitting.

nehešt (#)

Fr.: sédiment   

Mineral or organic material which has been transported and deposited by an agent of erosion such as water, wind, and ice.

From Fr. sédiment, from L. sedimentum "a settling, sinking down," from stem of sedere "to settle, sit"

Nehešt past stem of neheštan "to place, deposit," from ne- "down, below," → ni- (PIE), + heštan "to place, put" from Mid.Pers. hištan, hilidan "to let, set, leave, abandon;" Parthian Mid.Pers. hyrz; O.Pers. hard- "to send forth," ava.hard- "to abandon;" Av. harəz- "to discharge, send out; to filter," hərəzaiti "releases, shoots;" cf. Skt. srj- "to let go or fly, throw, cast, emit, put forth;" Pali sajati "to let loose, send forth."

nehešti (#)

Fr.: sédimentaire   

Of, pertaining to, or of the nature of sediment.

Adj. of → sediment.

sedimentary rock
  سنگ ِ نهشتی   
sang-e nehešti

Fr.: roche sédimentaire   

A rock composed of materials that were transported to their present position by wind or water. → Sandstone, → shale, and → limestone are sedimentary rocks.

sedimentary; → rock.

Sednâ (#)

Fr.: Sedna   

A trans-Neptunian object (numbered 90377) and a likely → dwarf planet, it is the most distant large object yet found orbiting the Sun. It is at present over 90 A.U.s away, 3 times as far as Pluto. Its precise diameter is unknown, probably 1,600-2,200 km (about 12-17% of Earth). Its estimated orbital period is 12,050 years. Formerly known as 2003 VB12

In Inuit mythology, Sedna (Inuktitut Sanna) is a goddess of the marine animals, especially mammals such as seals.

Sedov-Taylor phase
  فاز ِ سدوف-تیلور   
fâz-e Sedov-Taylor

Fr.: phase de Sedov-Taylor   

The second phase in the evolution of a → supernova remnant (SNR) occurring after the → free expansion phase. After the passage of the → reverse shock, the interior of the SNR is so hot that the energy losses by radiation are very small (all atoms are → ionized, no → recombination). The expansion is driven by the → thermal pressure of the hot gas and can therefore be regarded as → adiabatic; the → cooling of the gas is only due to the → expansion. Pressure forces accelerate the swept-up → interstellar medium (ISM) converting → thermal energy (which came from original explosion) into → kinetic energy of the → shell of swept-up mass. As the mass of the ISM swept up by the shell increases, it eventually reaches densities which start to impede the free expansion. → Rayleigh-Taylor instabilities arise once the mass of the swept-up ISM approaches that of the ejected material. This causes the SNR's ejecta to become mixed with the gas that was just shocked by the initial → shock wave. The Sedov-Taylor phase lasts some 104 years and is followed by the radiative or → snowplow phase. Also called → adiabatic phase.

After Sedov, L. (1959, Similarity and Dimensional Methods in Mechanics, New York, Academic Press) and Taylor, G. I. (1950, Proc. Roy. Soc. London, A, 201, 159 and 175); → phase.

Seebeck effect
  اسکر ِ زیبک   
oskar-e Seebeck

Fr.: effet de Seebeck   

An → electromotive force produced in a closed electric circuit formed by connecting conductors of different metals in series when the two junctions junctions are maintained at different temperatures. The circuit constitutes a → thermocouple.

Named for the German physicist Thomas Seebeck (1770-1831), who discovered the effect; → effect.

toxm (#)

Fr.: germe   

A small single crystal of a semiconductor from which is grown the large single crystal for the manufacture of semiconductor devices.

O.E. sed, sæd; cf. O.N. sað, O.S. sad, O.Fris. sed, M.Du. saet, O.H.G. sat, Ger. Saat; PIE base *se- "to sow."

Toxm "seed" (Tabari tim "seed; race," Laki tôm "seed"), from Mid.Pers. tôhm, tôhmak, tôm, tuxm "seed; extraction; descent;" Av. taoxman- "seed;" O.Pers. taumī:- "family;" cf. Skt. tókman- "offspring, children, race, child," tokma- "young shoot, young blade of corn."

seed nucleus
  هسته‌ی ِ تخم   
haste-ye toxm

Fr.: noyau germe   

A nucleus from which a variety of → fusion  → chain reactions derive in → stellar nucleosynthesis.

seed; → nucleus.


Fr.: seeing   

A measure of the blurring and degradation of the image of astronomical objects caused by → turbulence in the Earth's atmosphere, including the telescope environment. Seeing causes the images of stars to break up into → speckle patterns, which change very rapidly with time. See also → Fried parameter; → differential image motion monitor.

M.E. seen, from O.E. seon; cf. O.S., O.H.G. sehan, M.H.G., Ger. sehen, M.Du. sien, Goth. saihwan, from PIE base *sekw- "to see."

Šekân "wrinkle, plait; curl; rupture, breach," variant of šekan "fold, curl; ripples on water," from šekastan "to break, split;" Mid.Pers. škastan "to break;" Av. scind-, scand "to break, cleave;" Proto-Iranian *skand- "to break, cleave;" PIE sken- "to cut off."

seeing disk
  گرده‌ی ِ شکان، دیسک ِ ~   
gerde-ye šekân, disk-e ~

Fr.: tache de seeing   

The angular size of a stellar image for long exposures, as determined by the ratio λ/r0, where λ is the wavelength and r0 the typical size of → turbulence patches. → Fried parameter. The most common seeing measurement is the → full-width at half-maximumof the seeing disk. → Airy disk.

seeing; → disk.

seeing monitor
  پهره‌گر ِ شکان   
pahregar-e šekân

Fr.: moniteur de seeing   

An optical instrument that follows the variation of → atmospheric turbulence by continuously measuring the → seeing conditions.

seeing; → monitor.


Fr.: segment   

1) Of a line, that portion bounded by two points.
2) Of a circle, that portion of a plane bounded by an arc of the circle and its chord.
3) Of a sphere, the solid formed between two parallel planes that cut through a sphere.
4) In computer science, a portion of a program, often one that can be loaded and executed independently of other portions.

From L. segmentum "a strip or piece cut off," originally a geometric term, from secare "to cut" + -mentum "-ment."

Borank, from Kermâni borang "a slice (of fruit);" Borujerdi boleng "piece, section," ultimately from *brin-ka- (probable contracted forms Lari peng and pengi "portion or part of anything"), related to boridan "to cut off;" Mid.Pers. brīn-, blyn-, britan, brinitan "to cut off," Av. brī- "to shave, shear," brin- (with prefix pairi-); cf. Skt. bhrī- "to hurt, injure," bhrinanti "they hurt;" PIE base bhrei- "to cut, pierce."

<< < -sc 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 SS sta sta sta sta ste ste ste Sto str str stu sub sub suc sun sup sup sup sup sur swa syn syn > >>