An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



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Number of Results: 21 Search : iron
biotic environment
  پرگیر ِ زیستیک   
pargir-e zistik

Fr.: environnement biotique   

Ecology: The environment consisting of living organisms, which interact with each other and with their non-living surroundings.

Biotic adj. of → biotics; of → environment.

Xeiron (#)

Fr.: Chiron   

An object, discovered in 1977, which was initially assumed to be an asteroid, but subsequent observations showed it to be a weak comet with a detectable coma. Its orbit, lying now between those of Saturn and Uranus, is unstable on time scales of a million years.

In Gk. mythology, Xειρων (Cheiron or Chiron) was the wisest of the Centaurs; he was not a drunkard like other Centaurs. Chiron was tutor to Jason and Heracles. He was the only immortal centaur.

  ۱، ۲، ۳) پرگیر؛ ۳) زیستبوم   
1, 2, 3) pargir (#); 3) zistbum

Fr.: environnement   

1) An aggregate of surrounding → circumstances, → conditions, or → influences in which a thing is situated or is developed.
2) Computers: The entire set of conditions under which one operates a → computer, as it relates to the hardware, operating platform, or operating system.
3) Ecology: The totality of circumstances surrounding an → organism or group of organisms. More specifically, the combination of external physical conditions that affect and influence the growth, development, and survival of organisms.

From environ + -ment; the first component from Fr. environs, plural of O.Fr. environ "compass, circuit," from environ (adv.) "around," from en- "in" + viron "circle, circuit," from virer "to turn."

Pargir, from par- "around, surrounding," variant pirâ-circum- + gir agent noun and present stem of gereftan "to take, seize; to make prisoner; to intercept" (Mid.Pers. griftan; Av./O.Pers. grab- "to take, seize;" cf. Skt. grah-, grabh- "to seize, take," graha "seizing, holding, perceiving;" M.L.G. grabben "to grab," from P.Gmc. *grab; E. grab "to take or grasp suddenly;" PIE base *ghrebh- "to seize").
Zistbum, from zist "life, existence," → bio-, + bum "region, land, place," → eco-.

ferric iron
  آهن ِ فریک   
âhan-e ferrik

Fr.: fer ferrique, fer trivalent   

Iron in a plus-3 → oxidation state. Ferric iron needs to share three electrons with an oxygen molecule to make the ion neutral.

ferric; → iron.

ferrous iron
  آهن ِ فرور   
âhan-e fervar

Fr.: fer ferreux, fer bivalent   

Iron in a plus-2 → oxidation state.

ferrous; → iron.

âhan (#)

Fr.: fer   

A metallic → chemical element occurring abundantly in combined forms and used alloyed in a wide range of important tools and structural materials; symbol Fe. → Atomic number 26; → atomic weight 55.845; → melting point about 1,535°C; → boiling point about 2,750°C; → specific gravity 7.87 at 20°C; → valence +2, +3, +4, or +6. Iron is of critical importance to life, i.e. plants, humans, and animals. It occurs in hemoglobin, a molecule that carries → oxygen from the lungs to the tissues and then transports → carbon dioxide (CO2) back from the tissues to the lungs.
Iron has the highest nuclear → binding energy of all elements, and is therefore the most stable element. It is synthesized in → massive stars, and its occurrence ends the process of → thermonuclear reaction in stars. The resulting energy crisis leads to the destruction of the star through a → supernova explosion. It has several → radioactive isotopes with half-lives from 6 min (61Fe) to about 3 x 105 years (60Fe).

Iron, from O.E. isærn, from P.Gmc. *isarnan (cf. O.S. isarn, O.N. isarn, M.Du. iser, O.H.G. isarn, Ger. Eisen) "holy metal" or "strong metal," probably an early borrowing of Celt. *isarnon (cf. O.Ir. iarn, Welsh haiarn), from PIE *is-(e)ro- "powerful, holy," from PIE *eis "strong" (cf. Skt. isirah "vigorous, strong," Gk. ieros "strong").
The chemical symbol Fe, from L. ferrum "iron."

Âhan, Kurd. âsan, Mid.Pers. âhan; Av. aiianhaēna- "made of metal," from aiiah- "metal;" cf. Skt. áyas- "iron, metal;"  L. aes "brass;" Goth. aiz "bronze;" O.H.G. ēr "ore" (Ger. Erz "oar"); O.E. ora "ore, unworked metal," ar "brass, copper, bronze."

Iron Age
  عصر ِ آهن   
asr-e âhan (#)

Fr.: âge du fer   

The period generally occurring after the → Bronze Age, marked by the widespread use of iron. Its date and context vary depending on the country or geographical region. The Indo-European Hittites are the first people to work iron, in the Asia Minor, from about 1500 BC.

iron; → age.

iron convection zone (FeCZ)
  زنار ِ همبز ِ آهن   
zonâr-e hambaz-e âhan

Fr.: zone convective du fer   

A → convective zone close to the surface of → hot stars caused by a peak in the → opacity due to iron recombination. A physical connection may exist between → microturbulence in hot star atmospheres and a subsurface FeCZ. The strength of the FeCZ is predicted to increase with → metallicity and → luminosity, but decrease with → effective temperature. The FeCZ in hot stars might also produce localized surface magnetic fields. The consequence of the FeCZ might be strongest in → Wolf-Rayet stars. These stars are so hot that the → iron opacity peak, and therefore FeCZ, can be directly at the stellar surface or, better said, at the → sonic point of the wind flow. This may relate to the very strong → clumping found observationally in Wolf-Rayet winds, and may be required for an understanding of the very high → mass loss rates of Wolf-Rayet stars (See Cantiello et al. 2009, A&A 499, 279).

iron; → convection; → zone.

iron core
  مغزه‌ی ِ آهن   
maqze-ye âhan

Fr.: cœur de fer   

1) Electromagnetism: A bar of → soft iron that passes through a coil and serves to increase the → inductance of the coil.
2) The innermost part of some planets, such as Mercury, Venus, and Earth, which have a molten iron-rich core.
3) The end point in the evolution of stars with a mass above ~ 10 → solar masses. Such a star evolves in several stages over millions of years during which various → thermonuclear reactions take place in the star core. Each stage results in a core composed of heavier elements. The process ends when → silicon burning produces a core of iron-nickel. Since iron has the maximum → binding energy per → nucleon, the → nuclear fusion cannot proceed further. The iron core shrinks and heats up. It is maintained against → gravitational collapse by → electron degeneracy pressure, but it continues to grow as Si burning adds more iron. When the core reaches its → Chandrasekhar limit, it becomes unstable and undergoes the → core collapse.

iron; → core.

iron meteorite
  شخانه‌ی ِ آهنی   
šaxâne-ye âhani (#)

Fr.: météorite ferreux   

A meteorite which is composed mainly of iron mixed with smaller amounts of → nickel. Iron meteorites make up about 4.4% of all meteorites. See also → stony meteorite, → stony-iron meteorite.

iron; → meteorite.

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.

iron peak
  ستیغ ِ آهن   
setiq-e âhan

Fr.: pic du fer   

A maximum on the element-abundance curve in the vicinity of the iron → atomic number 26. The relative higher abundance of the → iron peak elements results from their being the end products of → nucleosynthesis in the interiors of → massive stars.

iron; → peak.

iron peak element
  بن‌پار ِ ستیغ ِ آهن   
bonpâr-e setiq-e âhan

Fr.: élémént du pic du fer   

A member of a group of elements with → atomic masses A about 40 to 60 that are synthesized by the → silicon burning process and appear in the → iron peak. They are mainly: → titanium (Ti), → chromium (Cr), → manganese (Mn), → iron (Fe), → cobalt (Co), and → nickel (Ni).

iron; → peak; → element.


Fr.: ironique   

1) Using words to convey a meaning that is the opposite of its literal meaning; containing or exemplifying irony: an ironic novel; an ironic remark.
2) Of, pertaining to, or tending to use irony or mockery; ironical (

irony; → -ic.

govâžé (#)

Fr.: 1) ironie; 2) ironiser   

1) The humorous or mildly sarcastic use of words to imply the opposite of what they normally mean. → ironic.
2) An instance of this, used to draw attention to some incongruity or irrationality (

From L. ironia, from Gk. eironeia "dissimulation, assumed ignorance," from eiron "dissembler," perhaps related to eirein "to speak."

Govâžé, ultimately from Proto-Ir. *ui-vac-, from *ui- prefix denoting "apart, away, out," cf. Av. vi-, O.Pers. viy-, Skt. vi- (Mod.Pers., e.g., gozidan, → select, gozaštan "to cross," → passage) + *uac- "to say, speak," → word; also govâžidan "to make irony of, to say ironically."

low-metallicity environment
  پرگیر ِ کم‌فلز   
pargir-e kamfelez

Fr.: environnement faible en métaux   

A medium in which chemical elements have abundances smaller than the solar values.

low; → metallicity; → environment.

metal-rich environment
  پرگیر ِ پرفلز   
pargir-e porfelez

Fr.: environnement riche en métaux   

An environment (→ galaxy, → nebula) whose → metallicity is larger than that of the → Milky Way galaxy.

metal; → rich; → environment.

Socratic irony
  گواژه‌ی ِ سقراطی، ~ سقراتی   
govâže-ye Soqrâti

Fr.: ironie socratique   

A means by which the pretended ignorance of a skillful questioner leads the person answering to expose his own ignorance (Collins).

Socratic; → irony.

soft iron
  آهن ِ نرم   
âhan-e narm

Fr.: fer doux   

Iron that has a low carbon content, in contrast to → steel. Because it is easily magnetized and demagnetized, it is used to make the cores of → solenoids and other electrical equipment.

soft; → iron.

stony-iron meteorite
  شخانه‌ی ِ سنگی-آهنی   
šaxâne-ye sangi-âhani

Fr.: sidérolithe, sidérolite   

Meteorites comprised of roughly equal amounts of → nickel/→ iron and → stone. They are divided into two groups: → pallasites and → mesosiderites. The stony-irons are thought to have formed at the core/mantle boundary of their parent bodies. The stony-irons account for less than 2% of all known meteorites. Also called → siderolite.

stony; → iron; → meteorite.

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