An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



<< < -it ang bis cit cre dim ele flu gra ima iso lum men nec opt per pri rad rel sim spe the uti vis > >>

Number of Results: 471 Search : ity
image quality
  چونای ِ وینه، ~ تصویر   
cunâ-ye vineh, ~ tasvir

Fr.: qualité d'image   

1) The degree of visibility of relevant → information in an image.
2) The → full-width at half-maximum of a long exposure stellar image obtained by an instrument mounted on a telescope observing in the presence of → seeing.

image; → quality.

nâžâvi (#)

Fr.: impureté   

A substance that is incorporated into a semiconductor material to provide free electrons (n-type impurity) or holes (p-type impurity).

Impurity, from im- negation prefix, → in-, + purity, O.Fr. pureté, from L.L. puritatem (nom. puritas) "cleanness, pureness," from purus "clean;" cf. Av. pūitika- "serving for purification," Mod.Pers. pâk "clean;" Skt. pavi- "to become clean," pávate "purifies, cleanses;" O.H.G. fouwen, fewen "to sift;" PIE base *peu- "to purify, cleanse."

Nâžâvi "impurity," from nâ- negation prefix, → in-, + žâv "pure" + -i noun suffix.

nâsâzgâri (#)

Fr.: incompatibilité   

1) The condition of two things being so different in nature as to be unable to exist together.
2) Logic: (Of two or more propositions) unable to be true simultaneously.

incompatible; → -ity.


Fr.: individualité   

The particular character, or aggregate of qualities, that distinguishes one person or thing from others (

individual; → -ity.

  ناهموگی، نابرابری   
nâhamugi, nâbarâbari

Fr.: inégalité   

1) A statement of the form a ≠ b, a > b, or a < b, asserting one quantity is greater than or less than another quantity. → equality.
2) An irregularity in the movement of a celestial object in its orbit about another which cannot be explained by their mutual gravitational attraction. Irregularities are often due to perturbation by other neighboring objects.

in-; → equality.

  بی‌پایان، بی‌پایانی   
bipâyân (#), bipâyâni (#)

Fr.: infini, infinité   

That quantity which is greater than any assignable quantity.

Noun form of → infinite.

nâhamgeni (#)

Fr.: inhomogénéité   

The condition or an instance of not being homogeneous.

in- "not" + → homogeneity.

initial singularity
  تکینی ِ آغازین   
takini-ye âqâzin (#)

Fr.: singularité initiale   

An instant of infinite density, infinite pressure, and infinite temperature where the equations of general relativity break down, if the standard Big Bang theory is extrapolated all the way back to time zero. → singularity.

initial; → singularity.


Fr.: insécurité   

The quality or state of being insecure; something insecure.

in-; → security.

nâpâydâri (#)

Fr.: instabilité   

The condition of a system when it is disturbed by internal or external forces. The system continues to depart from the original condition, in contrast to a stable system, which will return to its previous condition when disturbed.

From → in- "not" + → stability

instability strip
  نوار ِ ناپایداری   
navâr-e nâpâydâri

Fr.: bande de l'instabilité   

A narrow, almost vertical, band on the right hand side of the → main sequence in the → H-R diagram occupied by many different types of → pulsating stars (→ RR Lyrae, → Cepheids, → W Virginis, → ZZ Ceti). Stars traverse this region at least once after they leave the main sequence. The narrow temperature range of the instability strip corresponds to the stellar → effective temperature that can sustain → partial ionization zones, capable of maintaining stellar oscillations. The blue (hot) edge of the instability strip pertains to stars with surface temperatures hotter than ~ 7500 K. Because these stars have partial ionization zones too close to their surface, the pulsation mechanism is not active. The red (cooler) edge of the instability strip is determined by stars with a temperature lower than ~ 5500 K. In these stars convection prevents the build-up of heat pressure necessary to drive pulsations.

instability; → strip.

instantaneous velocity
  تندای ِ لحظه‌ای   
tondâ-ye lahze-yi

Fr.: vitesse instantanée   

The velocity of a particle at some one instant of time, or at some one point of its path. It can be defined as the limiting value of the average velocity when the second point is taken closer and closer to the first point.

instantaneous; → velocity.


Fr.: intensité   

General: The quality or condition of being intense.
Physics: Strength, as of energy or a force per unit of area, solid angle, time, etc.; e.g. → electric intensity; → magnetic intensity.

From → intense + → -ity.

Dartanuyi state, condition noun of dartanu, → intense.

intensity of a line
  درتنویی ِ خط   
dartanuyi-ye xatt

Fr.: intensité de raie   

The height of a spectral line above the continuum base.

intensity; → line.

intensity of radiation
  درتنویی ِ تابش   
datanuyi-e tâbeš

Fr.: intensité de rayonnement   

The rate of emitted energy from unit surface area through unit solid angle. The radiation from a surface has different intensities in different directions.

intensity; → radiation.

internal gravity wave (IGW)
  موج ِ گرانی ِ درونی   
mowj-e gerâni-ye daruni

Fr.: onde de gravité interne   

A wave generated inside a density-stratified fluid under the influence of → buoyancy forces. Known also as → gravity wave or internal wave.

internal; → gravity; → wave.


Fr.: interopérabilité   

The ability of different types of computers, networks, operating systems, and software applications to work together by exchanging and sharing information in a standardized, accurate, and effective manner.

inter-; → operability.

intrinsic luminosity
  تابندگی ِ درونگین   
tâbandegi-ye darungin

Fr.: luminosité intrinsèque   

The energy per second emitted by an astronomical object.

intrinsic; → luminosity.


Fr.: invalidité   

Lack of → validity.

invalid; → -ity.

iron opacity peak
  ستیغ ِ کدری ِ آهن   
setiq-e kederi-ye âhan

Fr.: pic d'opacité du fer   

A bump appearing in the plot of stellar → opacity versus temperature. The ionization of the heaviest → chemical elements, especially → iron, which is the most abundant heavy metal, produces a large number of weak spectral → absorption lines. These lines dominate the stellar opacity in the temperature range 105-106 K and furnish two local opacity peaks: a large peak around 2 × 105 K and a smaller one around 1.5 × 106 K (Rogers & Iglesias, 1992, ApJS 79, 507; Iglesias et al. 1992, ApJ, 397, 717).

iron; → opacity; → peak.

<< < -it ang bis cit cre dim ele flu gra ima iso lum men nec opt per pri rad rel sim spe the uti vis > >>