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

<< < "no abe acc act aff ama ani ant aps ast atm aut bar bif Boh bou cal car Cen chi Cla col com com Com con con con con con con con con con con con con cor cor Cou cur dec def Den det dif dim dis dis dou E-t edi ele ell ene ero exa exp ext fer Fla fra FU Gam geo gra gra had har hig Hub Hyp imp ind inf ins int int ion iro ite Kep lar lep lin lon lun mag mas mer mig mol Moo mut neg new New non non non nuc obs on- opt Ori oxi par per per phl pho Pla ple pol pos pre Pro pro pub qua rad rad rec red reg rem res rev rot Sak Sco sec seg sha sim sol sou sph sta ste Str sub sup T a the Tho tra tre tum uni vel vis wav wor > >>

Number of Results: 3079 Search : on
animation
  فرهنش   
farhaneš

Fr.: animation   

1) An act or instance of animating or enlivening; the state or condition of being animated.
2) The technique of imaging successive drawings or positions of cartoons to create an illusion of movement when the film is shown as a sequence.

animate; → -tion.

anion
  آنیون   
ânion (#)

Fr.: anion   

A → negatively charged → ion or → radical. Anions in a liquid subjected to electric potential are attracted toward the → anode. See also → cation.

From Gk. anienai "to go up," from an-, from → ana- "up," + -i-, from ire, eo "to go, walk," cf. Pers. ây-, → assembly, + -on, as in → ion.

annihilation
  نابودی   
nâbudi (#)

Fr.: annihilation   

The process in which the entire → mass of → two colliding → particles, one of → matter and one of → antimatter, is → converted into → radiant energy in the form of → gamma rays. See also → annihilation operator.

L. annihilatus, p.p. of annihilare "to reduce to nothing," from ad- "to" + nihil "nothing," from ne- "not" + hilum "small thing, trifle"

Nâbudi, from nâ- "not" + bud "to be, exist," from budan "to be, exist" + -i noun forming suffix.

annihilation operator
  آپارگر ِ نابودی   
âpârgar-e nâbudi

Fr.: opérateur d'annihilation   

In → quantum field theory, the operator that lowers → eigenstates one → energy level, contrarily to the → creation operator.

annihilation; → operator.

annual aberration
  بیراهش ِ سالانه   
birâheš-e sâlâné

Fr.: aberration annuelle   

The apparent, small displacement in position of a star during the year due to the → aberration of starlight. It depends on the → celestial latitude, and its maximum value is about 20''.50. See also → constant of aberration; → aberration orbit.

annual; → aberration.

annual apparent motion
  جنبش ِ سالانه‌ی ِ پدیدار   
jonbeš-e sâlâne-ye padidâr

Fr.: mouvement annuel apparent   

annual motion.

annual; → apparent; → motion.

annual equation
  هموگش ِ سالانه   
hamugeš-e sâlâné

Fr.: équation annuelle   

An irregularity in the Moon's orbit, which can amount to 11 degrees in a period of one year. It results from the Sun's disturbing effect on the motion of the Moon due to varying distance between them.

annual; → equation.

annual motion
  جنبش ِ سالانه   
jonbeš-e sâlâné

Fr.: mouvement annuel   

The annual apparent motion of the → Sun in the sky with respect to → fixed stars along the path called → ecliptic. The apparent annual motion is due to the → Earth's → revolution about the Sun. In the course of this motion, the Sun appears to shifts about 1° eastward per day.

annual; → motion.

annual variation
  ورتش ِ سالانه   
varteš-e sâlâné

Fr.: variation annuelle   

Generally, the variation of a quantity over a year. In particular the yearly change in the right ascension or declination of a star, produced by the combined effects of the precession of the equinoxes and the proper motion of the star.

annual; → variation.

anomalistic month
  ماه ِ پیرازمینی   
mâh-e pirâzamini

Fr.: mois anomalistique   

The time interval of 27.554 551 days (27d 13h 18m 33.2s), on average, between two successive passages of the Moon through the → perigee of its orbit.

Anomalistic from → anomaly.

Pirâzamini from pirâzamin, → perigee.

anomalous dispersion
  پاشش ِ ناسان   
pâšeš-e nâsân

Fr.: dispesrion anormale   

The phenomenon whereby the → refractive index of light in a medium changes rapidly with wavelength in the vicinity of an → absorption band. Hence the → dispersion curve of the substance shows marked deviations from → Cauchy's equation, in contrast with the behavior of → normal dispersion. On the shorter λ side of the absorption band the refractive index falls off more rapidly than required by Cauchy's equation representing values of n for visible light. On the long λ side of the absorption band the index is very high, decreasing at first rapidly and then more slowly as one goes beyond the absorption band.

anomalous; → dispersion.

anonymous
  انام، بینام   
anâm, binâm

Fr.: anonyme   

Having an unknown or unacknowledged name. → anonymous object.

L. annymus, from Gk. annumos "nameless," from → an- "without" + onoma, onuma "name". Compare with L. nomen, Skt. nama, Av. nama, Mod. Pers. nâm, PIE *nomen "name".

Anâm, from Persian → a-, an- "without" + nâm "name," as above. Binâm, from bi- "without" + nâm.

anonymous object
  بر‌آخت ِ انام، ~ بینام   
barâxt-e anâm, ~ binâm

Fr.: objet anonyme   

An → astronomical object which has not been catalogued.

anonymous; → object.

antibaryon
  پادباریون   
pâdbâriyon

Fr.: antibaryon   

The → antiparticle of a → baryon.

anti-; → baryon.

anticorona
  پاد‌افسر، شکوه   
pâdafsar, šokuh

Fr.: gloire   

Meteorology: Small, faintly colored rings of light surrounding the → antisolar point, seen when looking down at a water cloud. Same as glory.

Anticorona, from → anti- + → corona.

Pâdafsar, from pâd-, → anti- + afsar "corona."
Šokuh "glory."

anticorrelation
  پادهم‌باز‌آنش   
pâdhambâzâneš

Fr.: anticorrelation   

Statistics: The correlation coefficient of two random variables X and Y is in general defined as the ratio of the Cov(X,Y) to the two standard deviations of X and Y. It varies between 1 and -1 corresponding to complete correlation or anticorrelation.

Anticorrelation, from → anti- + → correlation.

Pâdhambâzâneš, from pâd-, → anti-, + hambâzâneš, → correlation.

anticyclone
  پادچرخند   
pâdcarxand

Fr.: anticyclone   

Meteo.: A weather phenomenon associated with atmospheric high pressure. In the Northern Hemisphere an anticyclone rotates in the clockwise direction. The rotation is caused by the movement of colder higher pressure air that is moving away from the poles toward the equator being affected by the rotation of the Earth.

anti-; → cyclone.

anticyclonic
  پادچرخندی   
pâdcarxandi

Fr.: anticyclonique   

Having a sense of rotation about the local vertical opposite to that of the Earth's rotation. In other words, → clockwise in the Northern Hemisphere, → counterclockwise in the Southern Hemisphere, and undefined at the equator. The opposite of → cyclonic (Meteorology Glossary, American Meteorological Society).

anticyclone; → -ic.

antimony
  آنتیمو‌آن   
ântimuân (#)

Fr.: antimoine   

A silver white metallic element of a flaky nature, extremely brittle, occurring in nature free or combined, symbol Sb. → Atomic number 51; → atomic weight 121.75; → meting point 630.74°C; → boiling point 1,750°C; → specific gravity (metallic form) 6.69 at 20°C. Antimony is recognized in compounds from antiquity, and as a metal since the 17th century. The minerals stibnite (Sb2S3) and stibine (SbH3) are two of a multitude of mineral species which were known in the ancient world. Antimony is a poor conductor of heat and electricity. It greatly increases the hardness of metals with which it makes → alloys. Its various unstable isotopes have a half-life of 16 min (Sb120) to 2.7 years (Sb125).

From M.E. antimonie, from M.L. antimonium, an alchemist's term, of obscure origin, maybe a Latinization of Gk. stimmi or stibi, probably ultimately from Egyptian stm "cosmetic powder" used to paint the eyelids. The chemical symbol, Sb, comes from the original name, stibium, which is derived from Gk. stibi for "mark," since it was used for blackening eyebrows and eyelashes. The name was changed from stibium to antimonium to antimony.

Ântimuân, loan from Fr. antimoine.

antineutron
  پادنوترون   
pâdnotron

Fr.: antineutron   

The → antiparticle of the → neutron. It has the same mass, → spin, and → electric charge (zero) as the neutron but has opposite → baryon number (+1 for neutron, -1 for the antineutron). This is because the antineutron is composed of → antiquarks, while neutrons are composed of → quarks. The antineutron consists of one up antiquark and two down antiquarks.

anti-; → neutron.

<< < "no abe acc act aff ama ani ant aps ast atm aut bar bif Boh bou cal car Cen chi Cla col com com Com con con con con con con con con con con con con cor cor Cou cur dec def Den det dif dim dis dis dou E-t edi ele ell ene ero exa exp ext fer Fla fra FU Gam geo gra gra had har hig Hub Hyp imp ind inf ins int int ion iro ite Kep lar lep lin lon lun mag mas mer mig mol Moo mut neg new New non non non nuc obs on- opt Ori oxi par per per phl pho Pla ple pol pos pre Pro pro pub qua rad rad rec red reg rem res rev rot Sak Sco sec seg sha sim sol sou sph sta ste Str sub sup T a the Tho tra tre tum uni vel vis wav wor > >>