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: 204
vary
  ۱) ورتیدن؛ ۲) ورتاندن   
vartidan

Fr.: changer, varier   

1) To undergo change in form, substance, appearance, etc.
2) To change or alter. → covariance.

M.E. varien, from O.Fr. varier, from L. variare "change, alter, make different," from varius "variegated, different, spotted."

Vartidan "to change," from Mid.Pers. vartitan "to change, turn" (Mod.Pers. gardidan "to turn, to change"); Av. varət- "to turn, revolve;" cf. Skt. vrt- "to turn, roll," vartate "it turns round, rolls;" L. vertere "to turn;" O.H.G. werden "to become;" PIE base *wer- "to turn, bend."

vector
  بردار   
bordâr (#)

Fr.: vecteur   

Any physical quantity which requires a direction to be stated in order to define it completely, for example velocity. Compare with → scalar.

From L. vector "one who carries or conveys, carrier," from p.p. stem of vehere "carry, convey;" cognate with Pers. vâz (in parvâz "flight"); Av. vaz- "to draw, guide; bring; possess; fly; float," vazaiti "guides, leads" (cf. Skt. vah- "to carry, drive, convey," vahati "carries," pravaha- "bearing along, carrying," pravāha- "running water, stream, river;" O.E. wegan "to carry;" O.N. vegr; O.H.G. weg "way," wegan "to move," wagan "cart;" M.Du. wagen "wagon;" PIE base *wegh- "to drive").

Bordâr "carrier," agent noun from bordan "to carry, transport" (Mid.Pers. burdan; O.Pers./Av. bar- "to bear, carry," barəθre "to bear (infinitive);" Skt. bharati "he carries;" Gk. pherein "to carry;" L. ferre "to carry;" PIE base *bher- "to carry").

vector analysis
  آنالس ِ برداری   
ânâlas-e bordâri

Fr.: analyse vectorielle   

The study of → vectors and → vector spaces.

vector; → analysis.

vector angular velocity
  بردار ِ تندای ِ زاویه‌ای   
bordâr-e tondâ-ye zâviye-yi

Fr.: vecteur de vitesse angulaire   

Of a rotating body, a vector of magnitude ω (→ angular velocity) pointing in the direction of advance of a right-hand screw which is turned in the direction of rotation.

vector; → angular; → velocity.

vector boson
  بوسون ِ برداری   
boson-e bordâri

Fr.: boson vectoriel   

In nuclear physics, a → boson with the spin quantum number equal to 1.

vector; → boson.

vector calculus
  افماریک ِ برداری   
afmârik-e bordâri

Fr.: calcul vectoriel   

The study of vector functions between vector spaces by means of → differential and integral calculus.

vector; → calculus.

vector density
  چگالی ِ بردار   
cagâli-ye bordâr

Fr.: densité de vecteur   

A → tensor density of → order 1.

vector; → density.

vector field
  میدان ِ برداری   
meydân-e bordâri (#)

Fr.: champ vectoriel   

A vector each of whose → components is a → scalar field. For example, the → gradient of the scalar field F, expressed by: ∇F = (∂F/∂x)i + (∂F/∂y)j + (∂F/∂z)k.

vector; → field.

vector function
  کریای ِ برداری   
karyâ-ye bordâri

Fr.: fonction vectorielle   

A function whose value at each point is n-dimensional, as compared to a scalar function, whose value is one-dimensional.

vector; → function.

vector meson
  مسون ِ برداری   
mesoon-e bordâri

Fr.: meson vectoriel   

Any particle of unit spin, such as the W boson, the photon, or the rho meson.

vector; → meson.

vector perturbation
  پرتورش ِ برداری   
partureš-e bordâri

Fr.: perturbation vectorielle   

The perturbation in the → primordial Universe plasma caused by → vorticity. These perturbations cause → Doppler shifts that result in → quadrupole anisotropy.

vector; → perturbation.

vector product
  فر‌آورد ِ برداری   
farâvard-e bordâri

Fr.: produit vectoriel   

Of two vectors, a vector whose direction is perpendicular to the plane containing the two initial vectors and whose magnitude is the product of the magnitudes of these vectors and the sine of the angle between them: A x B = C, C = |AB sin α|. The direction of C is given by the → right-hand screw rule. Same as → cross product. See also → scalar product.

vector; → product.

vector space
  فضای ِ برداری   
fazâ-ye bordâri (#)

Fr.: espace vectoriel   

A system of mathematical objects consisting of a set of (muultidimensional) vectors associated with a set of (one-dimensional) scalars, such that vectors can be added together and vectors can be multiplied by scalars while preserving the ordinary arithmetic properties (associativity, commutativity, distributivity, and so forth).

vector; → space.

Vega (α Lyr)
  واقع، نسر ِ واقع   
Vâqe', Nasr-e Vaqe' (#)

Fr.: Véga   

The brightest star in the constellation → Lyra and the 5th brightest star in the sky. It is an A type → main sequence star of visual magnitude 0.03. Vega is also one of the closer stars to the Earth, lying just 25.0 light-years away. Vega's axis of rotation is nearly pointing at the Earth, therefore it is viewed pole-on. Fast rotation has flattened Vega at its poles, turning it from a sphere into an oblate spheroid. The polar diameter of Vega is 2.26 times that of the Sun, and its equatorial diameter 2.75 solar. The poles are therefore hotter (10,150 K) than the equator (7,950 K).

Vega, from Ar. al-Waqi' contraction of an-Nasr al-Waqi' (النسر‌الواقع) "swooping eagle," from an-Nasr "eagle, vulture" + al-Waqi' "falling, swooping."

veil
  واشامه   
vâšâmé (#)

Fr.: voile   

1) A piece of opaque or transparent cloth worn by women as a covering for the head and shoulders.
2) Something that covers, screens, or conceals.

M.E. veile; O.Fr. voile "a head-covering" (also "sail"), from L. vela, plural of velum "curtain, covering; sail."

Vâšâmé "veil," variants vâšâm, bâšâmé, bâšâm, from Mid.Pers. *varšâmak (loaned in Arm. varšamak "veil, scarf"); cf. Sogd. wâršâmé "veil;" from Proto-Ir. *varšāmaka-, from *varšām-, from *varš-, from var- "to cover;" cf. Av. var- "to cover, conceal;" Skt. var- "to cover;" Mid.Pers. warr "garment," prefixed uzvâr-, uzvârdan "to uncover, show, apprehend, interprete;" Mod.Pers. šalvâr "trousers" (literally "thigh cover;" the first component šal "thigh," šelang "thigh; step, distance between feet when walking," cognate with Gk. skelos "leg"); Kurd. (Soriani) barg "cover; clothes," da barg girtin "to wrap in a cover."

Veil Nebula
  میغ ِ واشامه   
miq-e vâšâmé

Fr.: Nébuleuse du Voile   

A part of the → Cygnus loop, an old → supernova remnant.

veil; → nebula.

veiling
  واشامش   
vâšâmeš

Fr.: voilage   

1) General: An act of covering with or as if with a veil.
2) A weakening of the → spectral lines of a star that occurs when the spectral lines are filled in by → continuum emission or light from a → companion star.

Verbal noun from veil (v.).

Vela
  بادبان   
Bâdbân (#)

Fr.: Voile   

The Sail. A part of the constellation Argo in the Southern hemisphere, which was later divided into three parts, the others being Carina and Puppis. Vela is situated at about 10h right ascension, -50° declination. Abbreviation: Vel; Genitive: Velorum.

From L. vela, plural of velum "sail, curtain, covering," velare "to cover, veil."

Bâdbân "sail," literally "wind keeper," from bâdwind + -bân a suffix denoting "keeper, guard," sometimes forming agent nouns or indicating relation, → host.

Vela pulsar
  پولسار ِ بادبان، تپار ِ ~   
pulsâr-e Bâdbân, tapâr-e ~

Fr.: pulsar du Voile   

A pulsar with a short period (89 milliseconds) associated with the → Vela supernova remnant. It is approximately 1500 light-years distant. The Vela pulsar is one of the few pulsars detectable optically. Its optical flashes, of visual magnitude 26, were detected in 1977. Also named PSR 0833-45.

Vela; → pulsar.

Vela supernova remnant
  بازمانده‌ی ِ اَبَر-نو‌اَختر ِ بادبان   
bâzmânde-ye abar-now-axtar-e Bâdbân

Fr.: reste de supernova du Voile   

A → supernova remnant located in the southern Milky Way in the constellation → Vela. It has a large angular diameter of about 8° and lies 250 ± 30 pc away (Cha et al. 1999, ApJ 515, L25). Its overall emission is dominated by the interaction of the → supernova blast wave with the → interstellar medium. This SNR is also notable for a number of protrusions extending well beyond its rim, which were suggested to be fragments of ejecta from the supernova explosion. X-ray spectroscopy has since confirmed several of these protrusions to indeed be strongly enriched with ejecta. The age of the SNR is estimated to be ~11,000 years, based on the spin-down rate of the associated → Vela pulsar, but ages as large as 20,000-30,000 years have also been argued.

Vela; → supernova remnant.

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