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

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 218
wind vane
  بادنما   
bâdnemâ (#)

Fr.: girouette   

An object that is balanced on a rotating axis and indicates the direction of the wind. Also called a weather vane.

wind + vane "a blade, plate," O.E. fanafana "piece of cloth," O.H.G. fano, Ger. Fahne "flag, standard."

Bbâdnemâ "wind indicator," from bâd, → wind, + nemâ, from nemudan, → planetarium.

wind velocity
  تندای ِ باد   
tondâ-ye bâd

Fr.: vitesse de vent   

The speed at which the → stellar wind is forced away from the star. Wind velocities of → hot stars are directly measured from → P Cygni profiles, which indicate velocities from several hundred to several thousand km s-1. See also → escape velocity, → terminal velocity, → velocity law, → radiation-driven wind, → CAK model.

wind; → velocity.

winding problem
  پراسه‌ی ِ پیچش   
parâse-ye piceš

Fr.: problème d'enroulement   

The problem encountered in the explanation of the → spiral arms of galaxies if the material making up a spiral arm is static, that is remains in the arm. Since galaxies exhibit → differential rotation, stars near the center take less time to orbit the center than those farther from the center. The arm would, after a few → galactic rotations, become increasingly curved and wind around the → galaxy ever tighter until it ultimately disappears. This is inconsistent with observations.

window
  روزنه   
rowzané (#)

Fr.: fenêtre   

1) Anything likened to a window in appearance or function.
2) In particular, the wavelength region in the electromagnetic spectrum that is relatively unaffected by atmospheric absorption. → atmospheric windows; → infrared window; → optical window; → radio window.

Window literally "wind eye," from O.N. vindauga, from vindr, → wind, + auga, → eye.

Rowzané, from rowzan "window, aperture;" Mid.Pers. rocânak "window," rôšn "light; bright, luminous," from Av. raocana- "bright, shining, radiant," raocah- "light, luminous; daylight," related to Mod.Pers. ruz "day," from Mid.Pers. rôc, O.Pers. raucah-; akin to Skt. rocaná- "bright, shining," roka- "brightness, light;" Gk. leukos "white, clear;" L. lux "light" (also lumen, luna); PIE base *leuk- "light, brightness." The Persian words rowšan "bright, clear," foruq "light," and afruxtan "to light, kindle" also belong to this family, as well as the E. light, Ger. Licht, and Fr. lumière; forusorxinfrarouge.

window function
  کریای ِ روزنه   
karyâ-ye rowzané

Fr.: fonction fenêtre   

A function whose value is zero outside a given interval. Applications of window functions include signal filtering and spectral analysis. The various types of windw functions include: → rectangular window, cosine window, triangular window, Gaussian window, Hanning window, and so on.

window; → function.

wine
  می، باده، نبید   
mey (#), bâdé (#), nabid (#)

Fr.: vin   

The fermented juice of grapes, made in many varieties, such as red, white, sweet, dry, still, and sparkling, for use as a beverage, in cooking, in religious rites, etc., and usually having an alcoholic content of 14 percent or less (Dictionary.com).

M.E., O.E. win, cognate with O.H.G. win, Du. wijn, Ger. Wein, from L. vinum "wine," from PIE *woin-o-, related Gk. word oinos.

Mey, variant mol "wine;" Mid.Pers. mad, may "wine;" Av. maδu- "wine;" cf. Skt. madhu- "wine, sweet drink, sweet;" Gk. methy "wine;" O.C.S. medu; Lith. medus "honey;" O.Irish mid; Welsh medd; Breton mez "mead;" O.E. medu; E. mead "fermented honey drink;" Russ. medved "(honey-eater) bear."
Bâdé, from Mid.Pers. bâdag, from O.Pers. *bātu- "wine" (from bātu-gara- "cup, bowl"); cf. Khotanese Saka bātaa- "wine;" O.Pers. *batiaka- "cup, bowl" (cf. Pers. bâdiyé "bowl") loaned in Gk. batiaké "bowl, cup."
Nabid, "wine, date-wine," ultimately from Proto-Ir. *paH- "to drink;" cf. Av. paitīš- "drink" in vīspô.paitīš- "having all sorts of drinks;" pitu- "juice, food;" Wakhi puv-, pəv-, pit-; Sanglechi pöv-/pövδ- "to drink;" Skt. pā- "to drink;" Gk. pinein "to drink;" L. bibere "to drink," related to potare "to drink."

wing
  بال   
bâl (#)

Fr.: aile   

1) Either of the two limbs of a bird allowing her to fly. → Pegasus.
2) Either of the large flat structures in an aircraft's body that provide the main source of lift.
3) In spectroscopy, same as → line wing.

M.E. wenge from O.N. vængr "wing of a bird, aisle, etc." (cf. Dan., Swed. vinge "wing").

Bâl "wing," Mid.Pers. bâl, variant of par / parr "feather, " with the conversion of p to b and r to l; Av. parəna- "feather;" cf. Skt. parnam; O.H.G. farn "fern;" PIE pornom "feather."

Wing-Ford band
  باند ِ وینگ-فورد   
bând-e Wing-Ford

Fr.: bande de Wing-Ford   

A spectral feature at 9850-10200 Å appearing in the spectrum of some late-type → M dwarfs. It is attributed to iron hybrid (FeH), a typical signature of the atmospheres of the coolest stars.

First detected by R. F. Wing and W. K. Ford (1969, PASP 81, 527); → band.

winter
  زمستان   
zemestân (#)

Fr.: hiver   

The season beginning at the → winter solstice, about December 22 and lasting until the → vernal equinox, about March 21.

M.E., OE; cf. O.Fris., Du. winter, O.S., O.H.G. wintar, Ger. winter, Dan., Swed. vinter, Goth. wintrus "winter"),

Zemestân "winter," related to zam "cold," Mid.Pers. zam, zamistân "winter;" Av. zimô "winter;" cf. Skt. hima- "cold, frost;" Ossetic zymæg/zumæg "winter;" Gk. xeimon "winter;" L. hiems "winter;" Lith. ziema "winter;" PIE *gheim- "snow, winter."

winter solstice
  خوریستان ِ زمستانی   
xoristân-e zemestâni

Fr.: solstice d'hiver   

The moment in the northern hemisphere when the → Sun attains its lowest → declination of -23°26' (or -23°.44) with respect the → equator plane. It happens when the Earth's axis is orientated directly away from the Sun, on 21 or 22 December. During the northern winter solstice the Sun appears to be directly overhead at noon for places situated at → latitude 23.44 degrees south, known as the → tropic of Capricorn. The winter solstice can occur at any moment during the day. Two successive winter solstices are shifted in time by about 6 h. The winter solstice in the northern hemisphere is the → summer solstice in the southern hemisphere.

winter; → solstice..

wire
  سیم   
sim (#)

Fr.: fil   

A slender flexible thread or rod of metal.

M.E., O.E. wir, cf. O.N. viravirka "filigree work," Swed. vira "to twist," O.H.G. wiara "fine gold work."

Sim "wire," initially "strand of silver," from sim "silver," from Mid.Pers. asêm "silver," from Gk. asemon "without mark, uncoined, shapeless, formless," from argurion asemon "uncoined money." For semantic similarity, see → silver.

wisdom
  خرد   
xerad (#)

Fr.: sagesse   

Good judgment with respect to abstract truth or theoretical matters. For Zarathushtra (around 1500 B.C.), wisdom is the utmost attribute of God, whom he call Ahura Mazda "Wise Lord" (... the Lord, wise in His rule, ... - Y45.9). For Plato (c. 427-347 B.C.) wisdom is the virtue appropriate to the rational soul. For Aristotle (c. 384-322 B.C.) it is the highest intellectual virtue. And for Ferdowsi (c. 932-1020 A.D.) no one can praise wisdom to the level it deserves. → reason.

M.E.; O.E. wisdom, from wis "wise" + -dom. The first component is related to → vision and Pers. bin, didan "to see."

Xerad "understanding, judjement, intellect, wisdom;" Mid.Pers. xrad "reason, intellect, intelligence, wisdom, understanding;" O.Pers. xraθu- "wisdom;" Av. xratu- "intelligence, understanding, wisdom; will, purpose, council;" cf. Skt. krátu- "power, will-power;" Gk. kratos "power, strength."

WN Wolf-Rayet
  وُلف-رایه‌ی ِ WN   
Wolf-Rayet-e WN

Fr.: Wolf-Rayet WN   

A → Wolf-Rayet star whose spectrum is dominated by emission lines of ionized nitrogen: N II 3995 Å, N III 4634-4661 Å, N III 5314 Å, N IV 3479-3484 Å, N IV 4058 Å, N V 4603 Å, N V 4619 Å, and N V 4933-4944 Å. This type is divided in sub-types WN2 to WN11.

W short for Wolf-Rayet star, N for → nitrogen.

WN/WC star
  ستاره‌ی ِ WN/WC   
setâre-ye WN/WC

Fr.: étoile WN/WC   

An object showing signatures of both → WN Wolf-Rayet stars and → WC Wolf-Rayet stars in the same spectrum, originating from individual stars rather than from WN + WC → binary systems. Such a WN/WC signature implies that the surface composition of the star is → nitrogen and → carbon enriched. This hybrid state results from a mixing process between He-burning → convective core and the overlying nitrogen enriched layers. According to model predictions, this situation corresponds to a short transition phase, lasting 103 to 104 years, during which a WN star evolves into a WC star. The WN/WC stars so far detected are all of early types.

WN Wolf-Rayet; → WC Wolf-Rayet.

WN10 star
  ستاره‌ی ِ WN10   
setâre-ye WN10

Fr.: étoile WN10   

A → WN Wolf-Rayet star whose spectrum shows the following emission line characteristics: N III 4634-4641, 5314 Å as strong as N II 3995 Å, Balmer lines, He I with → P Cygni profile.

W, from → Wolf-Rayet; N, from → nitrogen; → star.

WN11 star
  ستاره‌ی ِ WN11   
setâre-ye WN11

Fr.: étoile WN11   

A → WN Wolf-Rayet star whose spectrum shows the following emission line characteristics: N II 3995 Å as strong as He II 4686 Å, N III 4634-4641, 5314 Å weak or absent, Balmer lines, He I with → P Cygni profile.

W, from → Wolf-Rayet; N, from → nitrogen; → star.

WN2 star
  ستاره‌ی ِ WN2   
setâre-ye WN2

Fr.: étoile WN2   

A → WN Wolf-Rayet star whose spectrum shows the following emission line characteristics: N V 4603, 4619 Å weak or absent,He II 4686 Å strong.

W, from → Wolf-Rayet; N, from → nitrogen; → star.

WN2.5 star
  ستاره‌ی ِ WN2.5   
setâre-ye WN2.5

Fr.: étoile WN2.5   

A → WN Wolf-Rayet star whose spectrum shows the following emission line characteristics: N V 4603, 4619 Å present, N IV 3479-3484, 4058 Å absent.

W, from → Wolf-Rayet; N, from → nitrogen; → star.

WN3 star
  ستاره‌ی ِ WN3   
setâre-ye WN3

Fr.: étoile WN3   

A → WN Wolf-Rayet star whose spectrum shows the following emission line characteristics: N IV 3479-3484, 4058 Å very weaker than N V 3479-3484, 4058 Å and N III 4634-4641, 5314 Å weak or absent.

W, from → Wolf-Rayet; N, from → nitrogen; → star.

WN3/O3 star
  ستاره‌ی ِ WN3/O3   
setâre-ye WN/O3

Fr.: étoile WN3/O3   

A new type of → Wolf-Rayet stars found in the → Large Magellanic Cloud (LMC). These stars have both strong → emission lines, as well as → He II lines and → Balmer lines in absorption and spectroscopically resemble a → WN3 and → O3V binary pair. However, they are visually too faint to be WN3+O3 V → binary systems. So far nine WN3/O3 types have been detected, making up ~ 6% of the population of LMC WRs. Their temperatures are estimated to be around 100,000 K, a bit hotter than the majority of → WN Wolf-Rayet stars (by around 10,000 K) although a few hotter WNs are known. The abundances are what you would expect for → CNO equilibrium. However, most anomalous are their → mass-loss rates which are more like that of an → O star than a WN star. While their evolutionary status is uncertain, their low mass-loss rates and → wind velocities suggest that they are not products of homogeneous evolution. It is possible instead that these stars represent an intermediate stage between O stars and WNs. Since WN3/O3 stars are unknown in the Milky Way, their formation would depend upon → metallicity (Neugent et al., 2017, arxiv:1704.05497).

WN3; → O3; → star.

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