# An Etymological Dictionary of Astronomy and AstrophysicsEnglish-French-Persian

## فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

### M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 1066
 parts per million (ppm)   پار در میلیون   pâr dar milionFr.: partie par million   A fraction of a whole number in units of 1/1000,000. It is usually used to describe chemical concentrations, very small amounts of pollutants in air, water, body fluids, and uncertainty. For example 30 ppm is 3 x 10-5 or 0.003%.→ part; → per; → million. pascal (Pa)   پاسکال   pâskâl (#)Fr.: pascal   The → SI unit of → pressure, that of one → newton per → square → meter. Since 1 Pa is a small pressure, hPa (→ hectopascals) are more widely used. 1 Pa = 10 dyn cm-2, = 1.02 x 10-5 kgf cm-2 = 10-5 bars = 9.87 x 10-6 atm = 7.50 x 10-3 torr (mm Hg).In honor of Blaise Pascal (1623-1662), French mathematician, physicist, and religious philosopher for his contribution in the study of hydrodynamics and hydrostatics, in particular establishing the principle of the barometer. Pascal's barrel experiment   آزمایش ِ چلیک ِ پاسکال   âzmâyeš-e celik-e PascalFr.: expérience du tonneau de Pascal   An experiment carried out by Blaise Pascal in 1646 to demonstrate the hydraulic pressure. A long and narrow vertical pipe was connected to the content of a closed wooden barrel already full of water. He poured a small quantity of water into the pipe, whereby the height of the fluid within the pipe sharply increased. Due to the increase in hydrostatic pressure and → Pascal's law, the barrel could leak and even burst.→ pascal (Pa); M.E. barel, from M.Fr. baril, O.Fr. barril; → experiment Pascal's law   قانون ِ پاسکال   qânun-e pâskâl (#)Fr.: loi de Pascal   A change in the pressure of an enclosed incompressible fluid is conveyed undiminished to every part of the fluid and to the surfaces of its container.Named after Blaise Pascal (1623-1662), French mathematician, physicist, and religious philosopher for his contribution in the study of hydrodynamics and hydrostatics, in particular establishing the principle of the barometer. Pascal's triangle   سه‌بر ِ پاسکال   sebar-e PascalFr.: triangle de Pascal   An array of numbers in the shape of a triangle, having a 1 at the top and also at the ends of each row. Each number is obtained by summing the two adjacent numbers to it in the preceding row. Each row is a set of → binomial coefficients. In the expansion of (x + y)n, the coefficients of x and y are given by the n-th row of Pascal's traingle.→ pascal; → triangle. Paschen series   سری ِ پاشن   seri-ye Paschen (#)Fr.: série de Paschen   The spectral series associated with the third energy level of the hydrogen atom. The series lies in the infrared, with Pα at 18,751 Å, and Paschen limit at 8204 Å.In honor of Friedrich Paschen (1865-1947), German physicist; → series. Paschen-Back effect   ا ُسکر ِ پاشن-بک   oskar-e Paschen-BackFr.: effet Paschen-Back   An effect on spectral lines obtained when the light source is located in a strong magnetic field. The strong field disrupts the coupling between the orbital and spin angular momenta, resulting in a different pattern of splitting.Named for the German physicists Friedrich Paschen (1865-1947) and Ernst E. A. Back (1881-1959); → effect. Pasiphae   پسیفاءه   PâsifâéFr.: Pasiphaé   The fifteenth of Jupiter's known satellites, orbiting at 23,660,000 km from Jupiter; also known as Jupiter VIII. Its diameter is 36 km and orbital period 744 days.In Gk. mythology, Pasiphae was the wife of Minos and mother, by a white bull, of the Minotaur. passage   گذر   gozar (#)Fr.: passage   An act or instance of passing from one place, condition, etc., to another; transit. Same as → transit.M.E, from O.Fr. passage, from passer "to go by;" originally "a road, passage."Gozar "passage, transit, passing," from gozaštan "to pass, cross, transit," variant gozâštan "to put, to place, let, allow;" Mid.Pers. widardan, widâštan "to pass, to let pass (by);" O.Pers. vitar- "to pass across," viyatarayam "I put across;" Av. vi-tar- "to pass across," from vi- "apart, away from" (O.Pers. viy- "apart, away;" Av. vi- "apart, away;" cf. Skt. vi- "apart, asunder, away, out;" L. vitare "to avoid, turn aside") + O.Pers./Av. tar- "to cross over;" → trans-. passband   گذرباند   gozar-bândFr.: bande passante   The range of wavelengths that are transmitted by a filter. Same as → band-pass.Pass from O.Fr. passer, from V.L. *passare "to step, walk, pass," from L. passus "step, pace;" cf. Pers. pâ "foot," pey "step;" → band.Gozar "passage, transit, passing," from gozaštan "to pass, cross, transit," variant gozâštan "to put, to place, let, allow;" Mid.Pers. widardan, widâštan "to pass, to let pass (by);" O.Pers. vitar- "to pass across," viyatarayam "I put across;" Av. vi-tar- "to pass across," from vi- "apart, away from" ( O.Pers. viy- "apart, away;" Av. vi- "apart, away;" cf. Skt. vi- "apart, asunder, away, out;" L. vitare "to avoid, turn aside") + O.Pers./Av. tar- "to cross over"); bând, → band. passive   اکار   akârFr.: passif   Tending not to participate actively; not working or operating.From L. passivus "submissive; capable of feeling or suffering," from passus, p.p. of pati "to experience, undergo, suffer."Akâr "not working, not doing," from → a- negation prefix + kâr "work," varaint of kar, present stem of kardan "to do, to make" (Mid.Pers. kardan; O.Pers./Av. kar- "to do, make, build;" Av. kərənaoiti "he makes;" cf. Skt. kr- "to do, to make," krnoti "he makes, he does," karoti "he makes, he does," karma "act, deed;" PIE base kwer- "to do, to make"). passive cloud   ابر ِ اکار   abr-e akârFr.: nuage passif   A cumulus cloud that is no longer dynamically connected with the atmospheric boundary layer via updrafts or downdrafts.→ passive; → cloud. passive component   همنه‌ی ِ اکار   hamne-y akârFr.: composante passive   An electronic component which contains no source of power, in contrast to active components.→ passive; → component. passive galaxy   کهکشان ِ اکار   kahkešân-e akârFr.: galaxie passive   A galaxy lacking optical emission-line activity (e.g., [O II], Hα, [O III]) and showing only stellar absorption lines (e.g., the 4000 Å → calcium break, Mg I, Na I). Also called passively evolving galaxy.→ passive; → galaxy. passive system   راژمان ِ اکار   râžmân-e akârFr.: système passif   An electronic system which emits no energy, and is not detectable.→ passive; → system. passively evolving galaxy   کهکشان با فرگشت ِ اکار   kahkešân bâ fargašt-e akârFr.: galaxie en évolution passive   Same as → passive galaxy.→ passive; → evolve; → galaxy. password   گذرواژ   gozarvâžFr.: mot de passe   An arbitrary string of characters chosen by a user or system administrator and used to authenticate the user when he attempts to log on, in order to prevent unauthorised access to his account (foldoc.org).Pass, → passage; → word. past   گذشته   gozašté (#)Fr.: passé   Of, having existed in, or having occurred during a time previous to the present; bygone (Dictionary.com).M.E.; variant spelling of passed, p.p. of pass, from O.Fr. passer, from V.L. *passare "to step, walk, pass," from L. passus "step, pace;" cf. Pers. pâ "foot," pey "step," → foot.Gozašté, p.p. of gozaštan "to pass," → passage. past participle   پارگرته‌ی ِ گذشته   pârgerte-ye gozaštéFr.: participe passé   A → participle that indicates a completed action or state.→ past; → participle. patch   پچ   pac (#)Fr.: pièce   1) A small piece of material used to mend a tear or break, to cover a hole, or to strengthen a weak place. 2) A piece of material used to cover or protect a wound, an injured part, etc. 3) A small piece, scrap, or area of anything (Dictionary.com). → bald patch; → patchy turbulence.M.E. pacche; of uncertain origin.Pac, from Bašgaridi (Giroft) pac "patch; fragment," probably from *parka-, from *par- "piece" + diminutive/relation suffix -ka; cf. pâré "piece, part, portion;" parré "portion, segment (of an orange);" pargâlé "piece, portion; patch;" Kermâni pariké "portion, half;" Tabari perik "minute quantity, particle;" Lârestâni pakva "patch;" Borujerdi parru "patch;" (Fin Bandar Abbâs) park "patch;" (Tâti) pajina "patch, darn;" → part.