An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A temperature scale in which the → freezing point and the → boiling point of → water are set to 0 and 80 degrees respectively. See also → Celsius scale, → Fahrenheit scale, → Kelvin scale, → Rankine scale.

Named after René Antoine Ferchault de Réaumur (1683-1757), who first proposed it in 1730; → scale.

1) To bound or spring back from force of impact.
2) The act of rebounding; recoil.

M.E., from O.Fr. rebondir "leap back, resound; push back," from → re- "back" + bondir "to leap, bound."

Vâjahidan, from vâ-, → re-, + jahidan "to leap, → jump."

A galaxy whose distance increases from other galaxies due to the global expansion of the Universe.

Receding, verbal adj. of recede, M.E., from M.Fr. receder, from L. recedere "to go back, withdraw," from → re- "back" + cedere "to go;" → galaxy.

Kahkašân, → galaxy; dur šavandé "receding," from dur, → far, + šavandé agent noun of šodan "to go, to pass; to become, to be, to be doing;" Mid.Pers. šudan, šaw- "to go;" Av. š(ii)auu-, šiyav- "to move, go," šiyavati "goes," šyaoθna- "activity; action; doing, working;" O.Pers. šiyav- "to go forth, set," ašiyavam "I set forth;" cf. Skt. cyu- "to move to and fro, shake about; to stir," cyávate "stirs himself, goes;" Gk. kinein "to move;" Goth. haitan "call, be called;" O.E. hatan "command, call;" PIE base *kei- "to move to and fro."

An electronic device that amplifies, detects, and gives a measure of the intensity of radio signals.

M.E. receven, from O.Fr. recoivre, from L. recipere from → re- + -cipere, combining form of capere "to take, hold, seize," PIE base *kap- "to grasp" (cf. Skt. kapati "two handfuls," Gk. kaptein "to swallow," O.Ir. cacht "servant-girl," lit. "captive," Goth. haban "have, hold," O.E. habban "to have, hold," probably Mod.Pers. qâp-, qâpidan, kapidan "to seize, rob," Av. haf-, hap- "to keep, observe").

Girandé, agent noun of gereftan "to take, seize, hold;" Mid.Pers. griftan, gir- "to take, hold, restrain;" O.Pers./Av. 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 *ghrebh- "to seize."

The unwanted signal affecting a receiver.

→ receiver; → noise.

1) Of, belonging to, or occurring at a time immediately before the present.
2) Geology: Of, belonging to, or denoting the Holocene Epoch.

From L. recentem (nominative recens) "fresh, new, young," from → re- + PIE root *ken- "fresh, new, young;" cf. Av. kainika-, kanya- "young girl;" Mod.Pers. kaniz(ak) "maid, virigin, girl; a female slave;" Mid.Pers. kanig, kanizag "girl, maid;" Gk. kainos "new;" Skt. kanina- "young;" Old Irish cetu- "first;" O.C.S. koni "beginning."

Tarné, from Tabari tarné "fresh, new, young, recent" (tarné mâr "fresh mother," i.e. "animal that has just given birth," tarné guk "recently born calf"), related to Pers. tar "fresh, young; wet," tarké "sprout;" Mid.Pers. tarr "fresh, moist;" Proto-Ir. *tarna-; cf. Av. tauruna- "young, fresh; young boy, lad;" Skt. táruna- "young, fresh;" Gk. teren "delicate, weak."

In the recent past.

→ recent + -ly a suffix forming adverbs from adjectives.

1) The property of having happened or appeared not long ago.
2) A time immediately before the present.

→ recent; → -ness.

1) The act of receding, going back, or withdrawing.
2) Economics: A period of an economic contraction, sometimes limited in scope or duration (Dictionary.com).

From Fr. récession "a going backward, a withdrawing," from L. recessionem "a going back," noun of action from p.p. stem of recedere "to go back, fall back; withdraw, retire," from → re- "back" + cedere "to go," → process.

Duršod, from dur, → remote, + šod "going," past stem of šodan "to go, to become," → change. Vâraveš, from vâ-, → re-, + raveš verbal noun of raftan "to go," → method.

The velocity with which an object moves away from another object or a reference point.

→ recession; → velocity.

1) General: Any theorem that expresses various reciprocal relations for the behavior of some physical systems, in which input and output can be interchanged without altering the response of the system to a given excitation.
2) In classical electromagnetism, the theorem stating that the current in a detector divided by the voltage at the source remains constant when source and detector are interchanged, as long as the frequency and all the impedances are left unchanged.

Reciprocity, from L. reciproc(us) "returning the same way, alternating" + → -ity; → theorem.

Farbin, → theorem; dosuyegi, quality noun of dosuyé nuanced term of dosu "two-sided," from do, → two, + su "direction, side," from Mid.Pers. sôk "direction, side."

An act of recognizing or the state of being recognized.

Verbal noun of → recognize.

1) To identify as something or someone previously seen, known, etc.
2) To identify from knowledge of appearance or characteristics (Dictionary.com).

→ re-; → cognition; → -ize.

1) To draw back; to rebound or fly back.
2) An act of recoiling. → Compton recoil.

M.E. recoilen, reculen, from O.Fr. reculer "to go back, recede, retreat," from V.L. *reculare, from L. → re- "back" + culus "backside."

Paszadan, from pas-, → back-, + zadan "to strike, beat, dash against," from Mid.Pers. zatan, žatan, O.Pers./Av. jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"), Skt. han- "to strike, beat" (hantar- "smiter, killer"), cf. Gk. theinein "to strike," L. fendere "to strike, push," Gmc *gundjo "war, battle;" PIE *g^when- "to strike, kill."

1) The process or result of combining again.
2) The capture of an electron by a positive ion. It is the inverse process to → ionization.

Verbal noun of → recombine.

A measure of the specific rate at which oppositely charged ions join to form neutral particles. It is given by the rate at which those ions recombine, divided by the product of the densities of the two species involved.

→ recombination; → coefficient.

A recombination radiation that is continuous over a range of frequencies. Same as → continuum emission.

→ recombination; → continuum.

Same as → recombination era.

→ recombination; → epoch.

The era some 380,000 years after the → Big Bang (at a → redshift of about 1,100), when the Universe had cooled sufficiently so that protons and electrons combined to form → neutral hydrogen in a process called → recombination. The temperature was about 3,000 K and the ionization fraction low enough for Universe to become transparent to light. Consequently matter and radiation decouple from one another because no further → scattering of the radiation occurs. The observation of the → cosmic microwave background radiation provides a means of studying the Universe at the recombination era. Also called recombination epoch and → decoupling era.

→ recombination; → era.

An → emission line in a spectrum produced in an → H II region when a free electron combines with an ionized atom to form a neutral atom or an ion of lower → ionization stage. Same as → free-bound emission.

→ recombination; → line.