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: 731
-ment
   -مان، -ش، -ای   
-mân, -eš, -i

Fr.: -ment   

A suffix of nouns indicating state, condition, or quality, or the result or product of an action.

From Fr., from L. -mentum.

-meter
   -سنج   
-sanj (#)

Fr.: -mètre   

A combining form meaning "measure," used in the names of instruments measuring quantity, extent, degree.

From Fr. -mètre; → meter.

Suffix -sanj, present stem of sanjidan "to measure; to compare," from Mid.Pers. sanjidan "to weigh," from present tense stem sanj-, Av. θanj- "to draw, pull;" Proto-Iranian *θanj-. Other terms from this base in Pers.: lanjidan "to pull up," hanjidan, âhanjidan "to draw out," farhang "education, culture."

-metry
   -سنجی   
-sanji (#)

Fr.: -métrie   

A suffix with the meaning "the process of measuring."

-meter + -y a suffix used in the formation of action nouns.

-sanji, from sanj, → -meter, + -i a suffix of verbal nouns.

M dwarf
  کوتوله‌ی ِ M   
kutule-ye M

Fr.: naine M   

A star whose spectrum is dominated by the absorption bands of → titanium oxide (TiO) and → vanadium oxide (VO) and has many neutral metal lines. The → effective temperature of M dwarfs ranges from about 3850 to 2600 K. They are low mass stars with masses ranging from 0.6 times that of the Sun at spectral type M0 to less than 0.1 → solar masses. M dwarfs are very abundant, they account for about 70-80% of stars in the → Galactic disk. The nearest star to the Sun, → Proxima Centauri, is an M dwarf.

M, letter of alphabet in the → Harvard classification; → dwarf.

M star
  ستاره‌ی ِ M   
setâre-ye M (#)

Fr.: étoile de type M   

A cool, red star of spectral type M with a surface temperatures of less than 3600 K. The spectra of M stars are dominated by molecular bands, especially those of TiO. Naked-eye examples are Betelgeuse and Antares.

M, letter of alphabet, → star.

M-type asteroid
  سیارک ِ گونه‌ی ِ M   
sayârak-e gune-ye M

Fr.: astéroïde de type M   

A type of → asteroid that consists of metallic → iron and displays high → albedo (0.10-0.18). M-type asteroids inhabit the middle part of the → asteroid belt.

M for → metallic; → type; → asteroid.

M16
     
M16

Fr.: M16   

An → open cluster in the constellation → Serpens associated with the → Eagle Nebula. It is usually mistakenly stated as being that nebula. Also called NGC 6611. First discovered by Philippe Loys de Chéseaux in 1745-6.

Object bearing the number 16 in the → Messier catalog.

Mach angle
  زاویه‌ی ِ ماخ   
zâviye-ye Mach

Fr.: angle de Mach   

Half of the vertex angle of the → Mach cone generated by a body in → supersonic flight. It is given by sin μ = (a/v), where a is the speed of the sound waves and v the velocity of the object. In terms of Mach number: μ = asin (1/M). The Mach angle diminishes with the object velocity. For M = 1 it is 90°, for M = 2, it is 30°, and for M = 5, its is 11.5°.

Mach number; → angle.

Mach cone
  مخروط ِ ماخ   
maxrut-e Mach

Fr.: cône de Mach   

The cone that confines the pressure disturbance created by a → supersonic object moving in a → compressible medium.

Mach number; → cone.

Mach disk
  گرده‌ی ِ ماخ، دیسک ِ ~   
gerde-ye Mach, disk-e ~

Fr.: disque de Mach   

Same as → shock diamond.

So named because Ernst Mach (1838-1916) was the first to record its existence.

Mach number
  عدد ِ ماخ   
adad-e Mach (#)

Fr.: nombre de Mach   

The ratio of the speed of a moving object to the → sound speed in the medium through which the object is traveling.

Named after the Austrian physicist Ernst Mach (1838-1916); → number.

Mach wave
  موج ِ ماخ   
mowj-e Mach

Fr.: onde de Mach   

The envelope of wave fronts created by a → supersonic source.

Mach number; → wave.

Mach's principle
  پروز ِ ماخ   
parvaz-e Mach

Fr.: principe de Mach   

The local → inertial frame and the → inertia of any body results from the distribution of all matter in the Universe. This principle has been neither confirmed nor refuted.

Mach number; → number.

machine
  ماشین   
mâšin (#)

Fr.: machine   

1) An apparatus consisting of interrelated parts with separate functions, used in the performance of some kind of work.
2) A device that transmits or modifies force or motion.

From M.Fr. machine "device, contrivance," from L. machina "machine, fabric, device, trick," from Doric Gk. makhana, Attic Gk. mekhane "device, means," related to mekhos "means, expedient," from PIE *maghana- "that which enables," from base *magh- "to be able, have power" (cf. O.C.S. mogo "be able," O.E. mæg "I can").

Mâšin, loanword from Fr.

MACHO
  مچو   
MACHO

Fr.: MACHO   

A collective term for objects that reside in the → halo of a galaxy (in particular → brown dwarfs) and which do not emit enough radiation to be detected from Earth. MACHOs can be spotted using the technique of → microlensing.

Acronym from Massive Astrophysical Compact Halo Objects.

Maclaurin series
  سری ِ مک‌لورن   
seri-ye Maclaurin

Fr.: série de Maclaurin   

A → Taylor series that is expanded about the reference point zero.

Named after Colin Maclaurin (1698-1746), a Scottish mathematician.

macro-
  درشت-   
dorošt- (#)

Fr.: macro-   

A combining form meaning "large, long, great, excessive," used in the formation of compound words; opposite of → micro-.

From Gk. makros "long, large," from PIE base *mak-/*mek- "long, thin" (cf. L. macer "lean, thin;" O.N. magr, O.E. mæger "lean, thin").

Dorošt "large; rough, fierce," from Mid.Pers. društ "harsh, coarse;" O.Pers. darš- "to dare," daršam (adv.) "mightily;" Av. darš- "to dare," darši-, daršita- "bold, strong;" cf. Skt. dhars- "to be bold, courageous, to attack," dhrsita- "bold, daring;" Gk. thrasys "bold;" O.E. durran; E. dare.

macrocosm
  درشت‌کیهان   
dorošt-keyhân

Fr.: macrocosme   

The great world or Universe; the Universe considered as a whole (opposed to → microcosm).
A representation of a smaller unit or entity by a larger one, presumably of a similar structure.

macro-; → cosmos.

macronova
  درشت-نووا، درشت-نو‌اختر   
dorošt-novâ, dorošt-now-axtar

Fr.: macronova   

A stellar → explosion with energies between those of a → nova and a → supernova and observationally distinguished by being brighter than a typical nova (MV ~ -8 mag) but fainter than a typical supernova (MV ~ -19 mag) (Kulkarni 2005; arXiv:astro-ph/0510256).

macro-; → nova.

macroscopic
  درشت‌بینیک   
dorošt-binik

Fr.: macroscopique   

Of or relating to scales large enough to be visible to the naked eye or under low order of magnification. Compare → microscopic. → microscopic state.

macro-; → -scope + → -ic.

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