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

<< < -ne nan nat nea neg nes neu New New nin noi non non nor nou nuc nuc num > >>

Number of Results: 360
natural language
  زبان ِ زاستاری   
zabân-e zâstâri

Fr.: langage naturel   

Linguistics: A language that has evolved naturally as a means of communication among people, as opposed to → artificial language and → formal language (Dictionary.com).

natural; → language.

natural line broadening
  پهنش ِ زاستاری ِ خط   
pahneš-e zâstâri-ye xatt

Fr.: élargissement naturel de raie   

The broadening of any spectral line due to the fact that excited levels have mean lives, which, by virtue of the uncertainty principle, implies a spread in the energy values.

natural; → line; → broadening.

natural logarithm
  لگاریتم ِ زاستاری   
logâritm-e zâstâri

Fr.: logarithme naturel   

The logarithm in which the → base is the → irrational number e = 2.718281828.... Also called → Napierian logarithm. The natural logarithm is denoted ln, an abbreviation of logarithmus naturalis. Natural logarithms are related to → common logarithms through: ln x = (1/M) log x, with M = (1/ln 10) ≅ 0.434294.

natural; → logarithm.

natural number
  عدد ِ زاستاری   
adad-e zâstâri

Fr.: nombre naturel   

Either a member of the set of positive integers 1, 2, 3, ..., or the set of non-negative integers 0, 1, 2, 3, ... There seems to be no general agreement about whether to include 0 in the set of natural numbers.

natural; → number.

natural period
  دوره‌ی ِ زاستاری   
dowre-ye zâstâri

Fr.: période naturelle   

Of a body or system, the period of → free oscillation.

natural; → period.

natural resonance
  باز‌آوایی ِ زاستاری   
bâzâvâyi-ye zâstâri

Fr.: résonance naturelle   

A resonance such that the period of the driving force is the same as the natural period of the system.

natural; → resonance.

natural satellite
  ماهواره‌ی ِ زاستاری   
mâhvâre-ye zâstâri

Fr.: satellite naturel   

A solar system → object that → revolves around a → primary body and is not man made.

natural; → satellite.

natural science
  دانش ِ زاستاری   
dâneš-e zâstâri

Fr.: science naturelle   

A science that deals with matter, energy, their interrelations and transformations, In other words, natural sciences are concerned with physical processes observable in nature. They can be divided into physical and biological sciences.

natural; → science.

natural units
  یکاهای ِ زاستاری   
yekâhâ-ye zâstâri

Fr.: unités naturelles   

Physical units of measurement defined in terms of universal physical constants in such a manner that some chosen physical constants (e.g. the speed of light, Planck's constant, Boltzmann's constant, etc.) are equal to unity. The use of natural units allows these constants to be omitted from mathematical equations, leading to simpler calculations.

natural; → unit.

natural uranium
  اورانیوم ِ زاستاری   
urâniom-e zâstâri

Fr.: uranium naturel   

Uranium as found in nature. It contains 0.7% uranium-235, 99.3% uranium-238, and a trace of uranium-234 by weight.

natural; → uranium.

naturalism
  زاستارگرایی، زاستارباوری   
zâstâr-gerâyi, zâstâr-bâvari

Fr.: naturalisme   

Philosophy: 1) The view of the world that takes account only of natural elements and forces, excluding the supernatural or spiritual.
2) The belief that all phenomena are covered by laws of science and that all teleological explanations are therefore without value (Dictionary.com).

natural; → -ism.

nature
  زاستار   
zâstâr

Fr.: nature   

The natural world as it exists without human beings or civilization.

M.E. natur(e), from O.Fr. nature from L. natura "the things at the outset, as it was when brought into existence; conditions of birth; essence, natural qualities," from natus "born," p.p. of nasci "to be born," from PIE *gen- "to give birth, beget," cognate with Pers. zâdan "to give birth," as below.

Zâstâr, literally "birth," from zâst past stem of [Dehxodâ] zâstan, variant of zâdan "to bring forth, give birth;" (Lâsgardi, Sorxeyi, Aftari) nestor "barren, sterile" (Mid.Pers. zâtan; Av. zan- "to bear, give birth to a child, be born," infinitive zazāite, zāta- "born;" cf. Skt. janati "begets, bears;" L. gignere "to beget," nasci "to be born," as above, PIE base *gen- "to give birth, beget") + suffix -âr (forming verbal nouns as in raftâr, kerdâr, goftâr, didâr, jostâr, and so on; or forming accusative nouns, as in gereftâr, koštâr, etc.).

nautical astronomy
  اخترشناسی ِ دریانوردیک   
axtaršenâsi-ye daryâ-navardik

Fr.: astronomie nautique   

The branch of practical astronomy concerned with the determination of position and direction on sea by observation of celestial objects.

Nautical, from M.Fr. nautique, from L. nauticus "pertaining to ships or sailors," from Gk. nautikos, from nautes "sailor," from naus "ship," from PIE *nau- "boat;" cf. Pers. nâv "ship;" O.Pers./Av. *nāv-, O.Pers. nāviyā- "fleet;" Skt. nau-, nava- "ship, boat;" → astronomy.

Axtaršenâsiastronomy; daryâ-navardik, relating to daryâ-navardi "sea navigation," from daryâ "sea" (Mid.Pers. daryâp variant zrah; O.Pers. drayah-; Av. zrayah- "sea;" cf. Skt. jráyas- "expanse, space, flat surface") + navardi, noun of navardidan, navardan "to travel, walk, pass by and over" + -ik, → -ic.

nautical twilight
  نیمتاب ِ دریانوردیک   
nimtâb-e daryâ-navardik

Fr.: crépuscule nautique   

The period before sunrise and after sunset when the center of the Sun's disk is between 6° and 12° below the horizon.

nautical astronomy; → twilight.

Navier-Stokes equation
  هموگش ِ ناویه-استوکس   
hamugeš-e Navier-Stokes

Fr.: équation de Navier-Stokes   

One of a set of differential equations that describes the motion of a fluid as a function of pressure, density, total external force, and viscosity. → Euler equation.

Named after Claude-Louis Navier (1785-1836), a French engineer and physicist, and George Gabriel Stokes (1819-1903), an English mathematician and physicist; → equation.

navigational astronomy
  اخترشناسی ِ ناورانی   
axtaršenâsi-ye nâvrâni

Fr.: astronomie nautique   

Same as → nautical astronomy.

Navigational, adj. of navigation, from L. navigationem (nom. navigatio), from navigatus, p.p. of navigare "to sail, steer a ship," from navis "ship," cognate with Pers. nâv "ship," as below, + root of agere "to drive," → act; → astronomy.

Axtaršenâsiastronomy; nâvrâni "navigation," from nâv "ship;" O.Pers./Av. *nāv-, O.Pers. nāviyā- "fleet;" cf. Skt. nau-, nava- "ship, boat" + râni verbal noun of rândan "to drive, to cause to go," causative of raftan "to go, walk, proceed" (present tense stem row-, Mid.Pers. raftan, raw-, Proto-Iranian *rab/f- "to go; to attack").

neap tide
  کهکشند   
kehkešand (#)

Fr.: marée de morte-eau   

Tide which occurs during the → first quarter and → third quarter of the → Moon when the pull of the Sun is at → right angles to that of the Moon.

Neap, from M.E. neep, from O.E. nepflod "neap tide" + → tide.

Kehkešan "small tide," from keh- "small, little," → low, + kešand, → tide.

near
  نزدیک   
nazdik (#)

Fr.: proche   

Close; to a point or place not far away.

O.E. near "closer, nearer," comparative of neah, neh "nigh."

Nazdik, from Mid.Pers. nazdik "near," from nazd "close" (Mid.Pers. nazd, nazdik "near," nazdist "first;" O.Pers. ašna- "close;" Av. nazdišta- "nearest, next," nazdyo "nearer to," nas- "to come near, approach, reach;" cf. Skt. nédīyas- "closer, very close," nas- "to approach, to reach") + -ik, → -ic.

near ultraviolet
  فرابنفش ِ نزدیک   
farâbanafš-e nazdik (#)

Fr.: proche ultraviolet   

The longest wavelengths of the ultraviolet region, which are adjacent to the visible, from 200 to 350 nm.

near; → ultraviolet.

near-Earth asteroid (NEA)
  سیارک ِ زمین-نزدیک   
sayyârak-e zamin-nazdik

Fr.: astéroïde géocroiseur   

An → asteroid whose orbit lies partly between 0.983 and 1.3 → astronomical units from the Sun, so that it passes close to the Earth. Currently thousands of near-Earth asteroids are known, ranging in size up to about 30 km. Among them, there are between 500 and 1,000 such asteroids larger than one km in diameter. They are divided into three subclasses: → Amor asteroids, → Apollo asteroids, and → Aten asteroids. See also → near-Earth object.

near; → earth; → asteroid.

<< < -ne nan nat nea neg nes neu New New nin noi non non nor nou nuc nuc num > >>