An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

   Homepage   
   


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

<< < -sc Sag sam sat sca sca Sch sco sec sec sec sei sel sem sep set Sha she sho sid sig sim sin sip ske sli Smo soc sol sol sol sol son sou Spa spa spe spe spe sph spi spo squ sta sta sta sta ste ste sti sto str str sub sub sub sum sup sup sup sup sur sus sym syn > >>

Number of Results: 1298
sidereal rotation period
  دوره‌ی ِ چرخش ِ اختری   
dowre-ye carxeš-e axtari

Fr.: période de rotation sidérale   

The rotation period of a celestial body with respect to fixed stars. For Earth, same as → sidereal day.

sidereal; → rotation; → period.

sidereal time
  زمان ِ اختری   
zamân-e axtari (#)

Fr.: temps sidéral   

The time based upon → Earth's rotation with respect to the stars, with the → sidereal day as the unit of measurement. At the moment when the → vernal equinox crosses the → meridian in → upper culmination, sidereal time is equal to zero hours for that observing position. The → hour angle of the vernal equinox is equal to sidereal time.

sidereal; → time.

sidereal year
  سال ِ اختری   
sâl-e axtari (#)

Fr.: année sidérale   

The interval between two successive passages of the Sun, in its apparent → annual motion around the → celestial sphere, through a particular point relative to stars. It is equal to 365.256356 days for the J2000.0 epoch and is 20m 24.5s longer than the → tropical year.

sidereal; → year.

siderite
  سیدریت   
siderit (#)

Fr.: sidérite   

1) A mineral composed of iron carbonate, FeCO3, that is a valuable ore of → iron.
2) A category of → meteorites consisting mainly of → iron and → nickel, commonly referred to as Irons. There are 13 different chemical groups of siderites. These groups are defined based on the relative abundance of nickel, gallium, germanium, and iridium. Irons are also categorized by their structural type.

From Gk. sider- variant of sidero- before a vowel, from sideros "iron" + -ite a suffix with several senses, specifically some minerals or chemical compounds.

siderolite
  سیدرولیت   
siderolit (#)

Fr.: sidérolithe, sidérolite   

The category of → meteorites commonly referred to as → stony-irons. The three classes of siderolites are → lodranites, → mesosiderites, and → pallasites.

From Gk. sidero-, from sideros "iron" + -lite a combining form used in the names of minerals.

siderophile
  آهندوست   
âhandust

Fr.: sidérophile   

Any → chemical element that prefers to combine with → iron rather than some other element.

From Gk. sidero-, from sideros "iron" + → -phile.

Âhandust, from âhan, → iron, + -dust, → -phile.

siderostat
  اخترداشتار   
axtardâštâr

Fr.: sidérostat   

A mirror arrangement with clock drive that reflects light from a celestial body to a fixed position. → coelostat; → heliostat.

From L. sidero-, from sidus (genitive sideris) "star, constellation" + -stat prefix denoting something that stabilizes, keeps, fixes, from -stata, from Gk. -states "one that causes to stand," or statos "standing," from *sta- "to stand."

Axtardâštâr, from axtar, → star, + dâštâr "holder, maintainer," from dâštan "to hold, maintain; to have; to possess;" Mid.Pers. dâštan; O.Pers./Av. dar- "to hold, keep back, maintain, keep in mind;" cf. Skt. dhr-, dharma- "law;" Gk. thronos "elevated seat, throne;" L. firmus "firm, stable;" Lith. daryti "to make;" PIE base *dher- "to hold, support."

siemens (S)
  زیمنس   
siemens (#)

Fr.: siemens   

The SI unit of electrical conductance, equal to the reciprocal of the ohm and replacing the equivalent MKS unit.

Named for the German electrical engineer Werner von Siemens (1816-1892).

sieve of Eratosthenes
  غربال ِ اراتوستنس   
qarbâl-e Eratosthenes (#)

Fr.: crible d'Eratosthène   

A classical method of finding all → prime numbers up to any given number n. The method consists of listing all positive integers from 2 up to the given number and then deleting some of them sequentially in steps. For example, if we wish to find the primes less than or equal to 50, we proceed as follows. All integers from 2 to 50 are first written. The integers that are divisible by 2, other than 2, are crossed out from the list. Since 3 is the first integer greater than 2 that is not removed, all the integers divisible by 3, other than 3, are crossed out. We do the same with 5 and then 7. Since all composite integers ≤ 50 are divisible by 2, 3, 5, or 7 (i.e. ≤ √50), all the remaining integers not deleted are prime numbers: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, and 47.

M.E. sive, O.E. sife "sieve;" cf. M.Du. seve, Du. zeef, O.H.G. sib, Ger. Sieb, of unknown origin. Related to sift; → Eratosthenes experiment.

Qarbâl (variants qarbil, qarbir, qelber, qalbur, gerbâl), probably related to the PIE base *krei- "to sieve, separate;" cf. Gk. krinein "to separate, decide, judge," krisis "decision;" L. cribrum "sieve" (Fr. crible), cernere "to sift, separate;" O.E. hriddel "sieve;" O.Ir. criathar; O.Welsh cruitr "sieve." Pers. qarbâl loaned in Ar. as gharbala "to sift," itself loaned in It. garbellare; M.Fr. garbeler "to sift;" E. garble "to sift impurities from."

sievert (Sv)
  سیورت   
sievert (#)

Fr.: sievert   

The SI unit for the dose equivalent of ionizing radiation. One sievert represents a dosage of 1 → joule per kg of tissue, absorbed from the ionizing radiation. The effect of radiation depends on its total amount of energy, the type of radiation, and the energy levels of particular particles. The dose equivalent in sieverts of radiation is the product of the absorbed dose in → gray (Gy)s and a dimensionless numeric factor, called the quality factor or relative biological effectiveness, dependent on the type of radiation. The sievert has replaced the → rem as the unit of dose equivalent. 1 rem = 10-2 Sv.

The unit honors the Swedish physicist Rolf Sievert (1898-1966), who worked over many years to measure and standardize the radiation doses used in cancer treatment.

sight
  دید   
did (#)

Fr.: visée   

The act or fact of seeing; field of vision. → line of sight.

M.E., from O.E. gesiht, gesihð "thing seen;" cf. Dan. sigte, Swed. sigt, M.Du. sicht, Du. zicht, O.H.G. siht, Ger. Sicht, Gesicht, related to → sign.

Did "sight, vision," past stem of didan "to see" (Mid.Pers. ditan "to see, regard, catch sight of, contemplate, experience;" O.Pers. dī- "to see;" Av. dā(y)- "to see," didāti "sees;" cf. Skt. dhī- "to perceive, think, ponder; thought, reflection, meditation," dādhye; Gk. dedorka "have seen").

sightline
  دید-خط   
did-xatt

Fr.: ligne de visée   

line of sight.

sight; → line.

sign
  نشان، نشانه   
nešân, nešâné (#)

Fr.: signe   

1) A conventional or arbitrary mark, figure, or symbol used as an abbreviation for the word or words it represents. Related terms: → signal, → signature, → symbol, → index.
2) Math.: A plus sign or minus sign used as a symbol for indicating addition or subtraction; also a sign for indicating the positive or negative value of a quantity.
3) → sign of the zodiac.

M.E., from O.Fr. signe "sign, mark, signature," from L. signum "mark, token, indication, symbol," from PIE base *sekw- "to see."

Nešân "sign, mark," from Mid.Pers. nišân "sign, mark, omen," nišitan "to gaze, stare, look into," niš in marv.niš "taking omen, foretelling, or divining from birds," nišak "clear, evident," from Proto-Iranian *niiaš- "to show," from *ni- "down, below," → ni- (PIE), + *iaš- "to show, appear;" cf. Armenian loanword niš "sign, mark, spot," loaned also in Syriac as nyš "sign" (Cheung 2007).

sign of the zodiac
  برج   
borj (#)

Fr.: signe du zodiaque   

One of the 12 constellations (in fact 13) making up the → zodiac.

sign; → zodiac.

Borj originally "tower," most probably related to Pers. borz "height, magnitude, greatness," boland "high," bâlâ "up, above, high, elevated, height," Laki dialect berg "hill, mountain;" Mid.Pers. burz "height," buland "high;" O.Pers. baršan- "height;" Av. barəz- "high, mount," barezan- "height;" cf. Skt. bhrant- "high;" L. fortis "strong" (Fr. and E. force); O.E. burg, burh "castle, fortified place," from P.Gmc. *burgs "fortress;" Ger. Burg "castle," Goth. baurgs "city," E. burg, borough, Fr. bourgeois, bourgeoisie, faubourg; PIE base *bhergh- "high." Borj may have been loaned into Ar. from Mid.Pers. The meaning extension of borj to its astronomical sense of zodiacal sign may have arisen from the conception of the zodiac as a barrier between heaven and Earth through which access was gained by means of twelve gates.

signal
  نشال   
nešâl

Fr.: signal   

1) Useful part of the received information that can be distinguished from noise.
2) Information transmitted by means of a modulated current or an electromagnetic wave and received by telephone, radio, television, etc.

M.E., from O.Fr. signal, from M.L. signale "a signal," from L.L. signalis (adj.) "used as a signal, pertaining to a sign," from L. signum "signal, sign."

Nešâl, from neš- base of nešân meaning → sign + -âl, → -al.

signal-to-noise ratio
  وابَر ِ نشال-به-نوفه   
vâbar-e nešâl-bé-nufé

Fr.: rapport signal sur bruit   

Concept used to quantify the effects of noise. It is the ratio of a signal to the standard deviation of the signal.

signal; → noise; → ratio.

signature
  نشانزد   
nešânzad

Fr.: signature   

1) Physics, Chem.: A distinctive trace or sign that indicates the presence of a substance or the occurrence of a physical process or event.
2) Telecommunication: The complete set of electromagnetic and/or acoustic signals received, e.g., from an infrared source, a radio or radar transmitter, an aircraft, or a ship. Signatures may consist of analog or digital signals, or both, and may be analyzed to indicate the nature of their source and assist in its recognition.

M.Fr. signature, from M.L. signatura "sign," in classical L. "the matrix of a seal," from signatus, p.p. of signare "to mark, sign," → sign.

Nešânzad, literally "striking a mark, sign" (cf. angošt zadan "fingerprint"), from nešân, → sign, + zad past stem of zadan "to strike, beat; to do; to play an instrument" (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").

significance
  نشاناری   
nešânâri

Fr.: significativité   

1) The state or quality of being significant; → meaning; importance.
2) Statistics: An estimated measure of the degree to which a result is not merely a matter of chance. See also → significance level, → significance testing.

From L. significantia "meaning, force, energy," from significans, present participle of significare, → signify.

Nešânâri, noun from nešânâr, → significant.

significance level
  تراز ِ نشاناری   
tarâz-e nešânâri

Fr.: niveau de significativité   

The level of → Type I error which one is willing to risk in a → test of significance. Also called level of significance.

significance; → level.

significance testing
  آزمون ِ نشاناری   
âzmun-e nešanâri

Fr.: test de significativité   

Statistics: A procedure that is used to decide whether to accept or reject the → null hypothesis or to determine whether observed samples differ significantly from expected results. Also called → test of significance and → rule of decision.

significance; → test.

<< < -sc Sag sam sat sca sca Sch sco sec sec sec sei sel sem sep set Sha she sho sid sig sim sin sip ske sli Smo soc sol sol sol sol son sou Spa spa spe spe spe sph spi spo squ sta sta sta sta ste ste sti sto str str sub sub sub sum sup sup sup sup sur sus sym syn > >>