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

A variable used in → spherical harmonic expansions. Each spherical harmonic is characterized by its multipole index l: l = 0 for a → monopole, l = 1 for a → dipole, and so on. It is used in particular to describe the → cosmic microwave background anisotropy: ΔT/T₀ (θ,φ) = Σ a_lmY_lm(θ,φ), where θ and φ are the → spherical polar coordinates, Y_lm is the → spherical harmonic functions, and the sum runs over l = 1, 2, ..., ∞ and m = -l, ..., l, where the multipole index l corresponds to angular scales ≅ 180°/l.

→ multipole; → index.

The quantity that gives the electric potential field due to a distribution of charges, such as a → dipole, → quadrupole, → octupole, etc. A multipole moment usually involves powers of the distance to the origin, as well as some angular dependence.

→ multi-; → pole; → moment.

1) A great number.
2) A great number of people gathered together; crowd; throng.
3) The state or character of being many; numerousness.

M.E., from O.Fr. multitude and directly from L. multitudo "a great number, a crowd; the common people," from multus "many, much," → multi-, + suffix -tudo "-tude."

Basiné, from basin + superlative of bas "many, much," → multi-, + suffix -in + -é noun/nuance suffix (as bišiné, kaminé, etc.).

Statistics: Having more than one → variable.

→ multi-; → variate.

A → time series consisting of two or more → univariate time series which share the same time period. As an example, if we record wind velocity and wind direction at the same instant of time, we have a multi-variate time series, specifically a bivariate one.

→ multivariate; → time; → series.

A → hypothetical set of → multiple universes, including our → Universe, that together comprise all of physical reality.

Initially coined by William James (1895) "an alternative to universe meant to convey absence of order and unity." In modern cosmology coined from -verse in → universe, by replacing uni- with multi- to denote "multiple universes."

Gitigân, from giti, → universe, + -gân multiplicity suffix.

Same as → Charpak's detector.

→ multi-; → wire; → proportional; → chamber.

A short-lived → elementary particle with negative → electric charge, represented by the symbol μ^-. The muon was discovered in 1936 by Carl Anderson (1905-1991) in → cosmic rays. It shares several properties with the electron: it is a → lepton with the same charge and → spin as the electron. But it is heavier than the electron (105 MeV/c²), about 200 times more massive. The muon is instable and decays after 2.197 × 10^-6 s into → electron, → neutrino, and → antineutrino (μ^-→ e^- + ν_μ + anti ν_e) .

A shortening of mu meson, from mu the 12th letter of the Gk. alphabet, + → meson.

An → instrument used in → geophysics to determine the average → density of geological bodies by measuring the → attenuation produced by → rocks on the flux of → atmospheric muons. This density muon → radiography is or example used to study the physical conditions inside → volcanoes.

→ muon; → telescope.

Of, relating to, or resembling a wall.

From M.Fr. muraille, from L. muralia, neut. pl. o f muralis "of a wall," from murus "wall."

Divâri "of a wall," from divâr "wall," from Mid.Pers. dîvâr "wall;" related to Mid.Pers. bâr, var "enclosure, defences, fortress;" Mod.Pers. bâru "wall, rampart, fortification; fort; tower;" O.Pers. didā- "wall, stronghold, fortress;" Av. var- "castle," from var- "to cover, conceil;" Proto-Iranian *dida-vāra-; cf. Skt. dehī- "wall;" Gk. teikhos "wall;" E. dike, ditch.

An angle measuring device mounted on or built into a wall. For astronomical purposes, these walls were oriented so they lie precisely on a meridian.

→ mural; → instrument.

A → mural instrument used to determine stellar positions. The quadrant consisted of a wall supporting a 90° graduated arc carefully oriented to the meridian. By means of a movable arm equipped with a sight, the altitude of a star could be determined at meridian passage.

→ mural; → quadrant.

1) The crime of unlawfully killing a person especially with malice aforethought.
2) To kill (a human being) unlawfully and with premeditated malice (Merriam-Webster).

M.E., from O.E. morðor "secret killing of a person, unlawful killing;" cf. O.Sax. morth, O.Fris. morth, O.Nor. morð, M.Du. moort, Du. moord, Ger. Mord "murder;" akin to Pers. mordan, marg, → death.

Qané, from Av. -γna- "slaying, strike;" Skt. ghana- "slaying;" Gk. phonos "murder;" Proto-Ir. *gan- "to strike to;" (Zazaki Kor) gin- "to strike, hit;" Ossetic (I.) qæn, (D.) ænæ "wound, fracture," also (D.) "guilt, transgression;" PIE *g^whono- "slaying."

One who murders; especially : one who commits the crime of murder (Merriam-Webster).

→ murder; → -er.

Having the purpose or capability of murder. Characterized by or causing murder or bloodshed (Merriam-Webster).

→ murder; → -ous.

The Fly. A minor constellation in the south → circumpolar region, lying south of → Crux, at 13h right ascension, 70° south declination. Its brightest star is of magnitude 2.7. Abbreviation: Mus; genitive: Muscae.

L. musca "fly" (Fr. mouche); Gk. muia "fly;" O.H.G. mucka "mosquito;" from PIE base *mu-.

Magas "a fly" (dialectal Aftari maqes; Tabari maqez, mahaz, maxši; Kurd. mêš, megez); Mid.Pers. magas, maxs "fly;" Av. maxši- "fly, mosquito;" cf. Skt. maśáka-, maks- "fly, mosquito;" PIE base *mako-.

1) A tissue composed of bundles of elongated cells capable of contraction and relaxation to produce movement in an organ or part.
2) An organ composed of muscle tissue (TheFreeDictionary.com).

From M.Fr. muscle "muscle, sinew" and directly from L. musculus "a muscle," literally "little mouse," diminutive of mus "mouse;" → -ule. So called because the shape and movement of some muscles (notably biceps) were thought to resemble mice.

Mâhice, literally "small fish, fish form," because of apparent resemblance of some muscles to fish, from mâhi, → fish, + -ce diminutive/similarity suffix; variant mâyce.

A sudden, random change in the genetic material of a cell. → commute.

From L. mutationem (nominative mutatio) "a changing," from mutatus, p.p. of mutare "to change," from PIE base *mei- "to change, go, move;" cf. Av. miθô "inverted, false," miθaoxta- "wrong spoken;" Skt. methati "changes, alternates, joins, meets," mith- "to alternate, meet," mithás "opposite, in opposition;" L. meare "to go, pass," mutuus "done in exchange;" Goth. maidjan "to change;" E. prefix mis- (in mistake).

Muteš, verbal noun of mutidan, from L. mutare, cognate with Av. miθô, as above, + -idan infinitive suffix.

1a) Silent; refraining from speech or utterance.
1b) Not emitting or having sound of any kind.
2a) To turn off (a microphone, a speaker, or audio.
2b) To muffle, reduce, or eliminate the sound of (Dictionary.com).

M.E. muet, mewet, muwet, from O.Fr. müet, muet "dumb, mute," from L. mutus "silent, dumb," ultimately from PIE imitative base *meue-; cf. Skt. mûka- "dumb;" Gk. mukos, mutis "dumb," myein "to be shut" (of the mouth); Iranian Khotanese mutä "dumb."

Xab, from Pers. xab "silent, mute," variants xape, xafe, xabak, xabâk "choked, strangled."

An inability to speak, due to a physical defect, conscious refusal, or psychogenic inhibition (Dictionary.com).

→ mute; → -ism.

Xabur, from xab, → mute, + -ur a possession suffix (as in ranjur, ganjur) variant of -var.