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

The part of → astrophysics that searches and studies → extrasolar planets.

→ exoplanet; → -logy.

The postulate that the concentrations of matter in the Universe follow a → fractal structure over a wide range of scales.

→ fractal; → cosmology.

A model of the Universe in which the Earth is centrally located and the Sun, planets, and stars revolve around the Earth.

→ geocentric; → cosmology.

The scientific study of the composition, structure, and physical history of the Earth.

→ geo- + → -logy.

A model of the Universe in which the Sun was centrally located.

→ heliocentric; → cosmology.

The branch of astrophysics that investigates the interior structure of the Sun by studying its surface wave oscillations. See also → asteroseismology and → stellar pulsation. The surface of the Sun vibrates much like a bell. A piano has 88 keys or musical tones, whereas the Sun has millions of notes. These vibrations are the result of internal pressure waves that reflect off the → photosphere and repeatedly cross the solar interior. They are detected through the → Doppler shift of absorption lines formed in the photosphere. Because these vibrations make the solar surface move up and down, analysis of the surface patterns is used to study conditions far below the Sun's surface. The mean period of the vibrations is about five minutes, which corresponds to a speed of 0.5 km s^-1 or a frequency of about 3 mHz. See also → p mode.

From → helio- + → seismology.

A cosmology characterized by clustering of galaxy clusters in increasingly larger systems.

→ hierarchical; → cosmology.

The study of the waters of the earth, especially with relation to the effects of precipitation and evaporation upon the occurrence and character of water in streams, lakes, and on or below the land surface.

Hydrology, from → hydro-; + → -logy.

A branch of medicine that deals with the diagnosis, management and treatment of various infectious or contagious diseases.

→ infection; → -logy.

The science and activity of receiving, storing, processing, and transmitting information by using → computers.

→ information; → technology.

An approach in which terms reconstructed in the → proto-language are used to make inferences about its speakers' culture and environment.

→ language;→ paleontology.

A branch of → linguistics that studies the formation, meaning, and use of words and their idiomatic combinations. In contrast to → terminology, lexicology is based on words and does not conceive of meaning unless it is related to the word.

From lexic, from Gk. lexicon, noun use of lexikos "pertaining to words," from lexis "word; speech" (+ -ikos, → -ics), from legein "to say, speak, recount," + -o-, + → -logy.

Vâžešnâsi, from vâžé, → word, + -šenâsi, → -logy.

The study of the → Moon's → crust, → rocks, strata (→ stratum), etc.

→ lunar; → geology.

Combined study of the large-scale → magnetic field (→ magnetometry) and → stellar pulsations (→ asteroseismology). Magneto-asteroseismology provides strong complementary diagnostics suitable for detailed stellar modeling and permits the determination of the → internal structure and conditions within → magnetic massive  → pulsators, for example the effect of magnetism on → mixing processes. More specifically, asteroseismology yields information on the → density, → composition, and → chemical mixing in multiple internal layers (depending on the number of studied frequencies). Additionally, when rotationally split pulsation modes are observed, the internal rotation profile can be retrieved. From magnetometry surface properties are determined, related to the → chemical composition, including → starspots, and the magnetic field, such as its geometry, obliquity, and strength. Magnetic studies also provide constraints about the → stellar wind geometry and the → circumstellar environment. Moreover, the stellar → rotation period period and the → angle of inclination toward the observer are also retrieved (Buysschaert et al., 2017, astro-ph/1709.02619).

→ magneto-; → asteroseismology.

The study of the physics, chemistry, and dynamics of the Earth's atmosphere, including the related effects at the air-earth boundary over both land and the oceans.

From Gk. meteorologia "discussion of celestial phenomena," from meteoron→ meteor + -logia, &rarr-logy.

Havâšenâsi, from havâ "weather, air," → air.

The science of measurement, embracing both experimental and theoretical determinations at any level of uncertainty in any field of science and technology.

From metro-, a combining form meaning "measure," → meter, + → -logy.

Andâze-šenâsi, from andâzé, → measure, + -šenâsi, → -logy.

1) The study of the form or → structure of anything.
2) The → form and structure of a whole entity under study.
3) Linguistics: The structure of → words in a → language, including patterns of → inflections and → derivation. The study and description of such structures.

From Gk. morphe "form, shape, outward appearance" + → -logy.

Rixt "shape, the way something is cast, as in founding," past stem of rixtan "to cast; to pour; to flow" (Mid.Pers. rēxtan and rēcitan "to flow;" Av. raēk- "to leave, set free; to yield, transfer," infinitive *ricyā; Mod.Pers; rig in morderig "heritage" (literally, "left by the dead"); cf. Skt. rinakti "he leaves," riti- "stream; motion, course;" L. rivus "stream, brook;" Old Church Slavic rēka "river;" Rus. reka "river;" Goth. rinnan "run, flow," rinno "brook;" O.E. ridh "stream." šenâsi, → -logy.

An observationally determined relationship between the → morphological classification of galaxies and the → environments in which they are located. Specifically, the morphology-density relation indicates that early-type galaxies (→ ETG) are preferentially located in high density environments, whereas late-type galaxies (→ LTG) are preferentially found in low density environments. Hence, spiral galaxies are rare in the high densities of clusters and are common in the lower density group environments. Early-type galaxies, on the other hand, are common in clusters and are rarely found in isolation.

→ morphology; → density; → relation.

The science and technology of producing and exploiting structures and systems at dimensions of roughly 1 to 100 → nanometers, that is those of single atoms and molecules. Materials with such minute structures possess mechanical, optical, chemical, magnetic or electronic properties not found in ordinary materials.

→ nano-; → technology.

The branch of meteorology that deals with clouds.

From Gk. nephos "cloud," nephele "cloud;" cognate with Pers. nam "moisture;" Av. napta- "moist," nabās-cā- "cloud," nabah- "sky;" L. nebula "mist," nimbus "rainstorm, rain cloud;" Skt. nábhas- "moisture, cloud, mist;" O.H.G. nebul; Ger. Nebel "fog;" O.E. nifol "dark;" PIE base *nebh- "cloud, vapor, fog, moist, sky" + → -logy.

Abršenâsi, from abr "cloud," from Mid.Pers. awr, abr (Laki owr, Baluchi haur, Kurd. Soriani hewr); Av. awra- "rain cloud, rain;" cf. Skt. abhra-"thunder cloud;" Gk. afros "scum, foam;" L. imber "rain;" also Sk. ambha- "water;" Gk. ombros "rain," PIE *mbhros "rain cloud, rain," from *mbh- + -šenâsi→ -logy.