An Etymological Dictionary of Astronomy and Astrophysics

PIE prefix *ni- “down, below.”

Etymology (EN): E. nether is from this PIE root; M.E. nethere, O.E. neothera, nithera “down, downward, below, beneath” (cf. O.S. nithar, O.N. niðr, O.Fris. nither, Du. neder, Ger. nieder); akin to Pers. ne-, ni-, as below.

Etymology (PE): Mod.Pers. ne-, ni- “down, below” (as in negâh “look, watch,” nešastan “to sit down,” nehoftan “to conceal,” nehâdan “to place, put,” nemudan “to display,” nefrin “curse,” etc.); Mid.Pers. ni-, O.Pers. preposition and verbal prefix ni- “down;” Av. nī- “down, in, into;” cf. Skt. ni- “down,” nitaram “downward;” Gk. neiothen “from below” (from ne-[io]- “below” + -then “from, since;” other usage examples of -then: po-then “from where,” paidio-then “since childhood,” panta-ho-then “from everywhere.”); E. nether, as above.

PIE prefix *ni- “down, below.”

Etymology (EN): E. nether is from this PIE root; M.E. nethere, O.E. neothera, nithera “down, downward, below, beneath” (cf. O.S. nithar, O.N. niðr, O.Fris. nither, Du. neder, Ger. nieder); akin to Pers. ne-, ni-, as below.

Etymology (PE): Mod.Pers. ne-, ni- “down, below” (as in negâh “look, watch,” nešastan “to sit down,” nehoftan “to conceal,” nehâdan “to place, put,” nemudan “to display,” nefrin “curse,” etc.); Mid.Pers. ni-, O.Pers. preposition and verbal prefix ni- “down;” Av. nī- “down, in, into;” cf. Skt. ni- “down,” nitaram “downward;” Gk. neiothen “from below” (from ne-[io]- “below” + -then “from, since;” other usage examples of -then: po-then “from where,” paidio-then “since childhood,” panta-ho-then “from everywhere.”); E. nether, as above.

Metallic chemical element belonging to the iron group; symbol Ni. Atomic number 28; atomic weight 58.69; melting point about 1,453°C; boiling point about 2,732°C. It was discovered by the Swedish metallurgist Axel-Fredrik Cronstedt (1722-1765) in 1751.

See also: Nickel, from shortening of Swedish kopparnickel “copper-colored ore,” from which it was first obtained, a half-translation of Ger. Kupfernickel, literally “copper demon,” from Kupfer “copper” + Nickel “demon, rascal” (from Nikolaus; cf. E. Old Nick “the devil;” the ore so called by miners because it looked like copper but yielded none.

Metallic chemical element belonging to the iron group; symbol Ni. Atomic number 28; atomic weight 58.69; melting point about 1,453°C; boiling point about 2,732°C. It was discovered by the Swedish metallurgist Axel-Fredrik Cronstedt (1722-1765) in 1751.

See also: Nickel, from shortening of Swedish kopparnickel “copper-colored ore,” from which it was first obtained, a half-translation of Ger. Kupfernickel, literally “copper demon,” from Kupfer “copper” + Nickel “demon, rascal” (from Nikolaus; cf. E. Old Nick “the devil;” the ore so called by miners because it looked like copper but yielded none.

Optical device constructed from a crystal of calcite, used for obtaining plane polarized light.

See also: Named after John Pringle Nicol (1804-1859), British physicist; → prism.

Optical device constructed from a crystal of calcite, used for obtaining plane polarized light.

See also: Named after John Pringle Nicol (1804-1859), British physicist; → prism.

The period between → sunrise and → sunset, especially the hours of darkness.

Etymology (EN): M.E., from O.E. niht (O.H.G. naht, Du., Ger. Nacht, O.N. natt, Goth. nahts), from PIE *nok(w)t- “night;” cf. Gk. nuks; L. nox (Fr. nuit; Sp. noche);
Skt. nákt-; Av. *naxtar- “night,” upa.naxtar- “adjoining the night” (Kurd. Soriani nûtak (?) “sheer darkness”); Lith. naktis; Russ. noch’.

Etymology (PE): Šab, from Mid.Pers. šab, šap “night;” O.Pers. xšap- “night;” Av. xšapan-, xšafn-, xšap- “night;” cf. Skt. ksáp- “night;” PIE base *k(w)sep- “night.”

The period between → sunrise and → sunset, especially the hours of darkness.

Etymology (EN): M.E., from O.E. niht (O.H.G. naht, Du., Ger. Nacht, O.N. natt, Goth. nahts), from PIE *nok(w)t- “night;” cf. Gk. nuks; L. nox (Fr. nuit; Sp. noche);
Skt. nákt-; Av. *naxtar- “night,” upa.naxtar- “adjoining the night” (Kurd. Soriani nûtak (?) “sheer darkness”); Lith. naktis; Russ. noch’.

Etymology (PE): Šab, from Mid.Pers. šab, šap “night;” O.Pers. xšap- “night;” Av. xšapan-, xšafn-, xšap- “night;” cf. Skt. ksáp- “night;” PIE base *k(w)sep- “night.”

A specialized technician in an observatory who is in charge of functioning a telescope and helping visiting astronomers during their observation run.

Etymology (EN): From → night + assistant; M.E. assistent, from L. assistent-, stem of assistens, pr.p. of assistere “assist, stand by,” from → ad- “to” + sistere “take a stand, cause to stand,” cognate with Pers. istâdan “to stand,” → histogram.

Etymology (PE): Dastyâr “assistant,” from dast “hand” (Mid.Pers. dast; O.Pers. dasta-; Av. zasta-; cf. Skt. hásta-; Gk. kheir; L. praesto “at hand;” Arm. jern “hand;” Lith. pa-žastis “arm-pit;” PIE *ghes-to-) + yâr “helper; companion” (Mid.Pers. hayyâr “helper,” hayyârêh “help, aid, assistance,” Proto-Iranian *adyāva-bara-, cf. Av. aidū- “helpful, useful”).

A specialized technician in an observatory who is in charge of functioning a telescope and helping visiting astronomers during their observation run.

Etymology (EN): From → night + assistant; M.E. assistent, from L. assistent-, stem of assistens, pr.p. of assistere “assist, stand by,” from → ad- “to” + sistere “take a stand, cause to stand,” cognate with Pers. istâdan “to stand,” → histogram.

Etymology (PE): Dastyâr “assistant,” from dast “hand” (Mid.Pers. dast; O.Pers. dasta-; Av. zasta-; cf. Skt. hásta-; Gk. kheir; L. praesto “at hand;” Arm. jern “hand;” Lith. pa-žastis “arm-pit;” PIE *ghes-to-) + yâr “helper; companion” (Mid.Pers. hayyâr “helper,” hayyârêh “help, aid, assistance,” Proto-Iranian *adyāva-bara-, cf. Av. aidū- “helpful, useful”).

An eye disease which is the difficulty in seeing at night or in dim light. Opposite of → hemeralopia. Also called → nyctalopia.

See also: → night; → blindness.

An eye disease which is the difficulty in seeing at night or in dim light. Opposite of → hemeralopia. Also called → nyctalopia.

See also: → night; → blindness.

Same as → airglow.

See also: → night; → glow.

Same as → airglow.

See also: → night; → glow.

A yellow star of visual magnitude 2.84, the second brightest in the constellation → Lepus. It is a giant of → spectral type G5, lying some 159 light-years away. Nihal is double, with a companion, 2.5 seconds of arc apart.

See also: From Ar. an-nihal (النهال) “the thirsty camels, drinking camels,” plural form of an-nâhil (الناهل).

A yellow star of visual magnitude 2.84, the second brightest in the constellation → Lepus. It is a giant of → spectral type G5, lying some 159 light-years away. Nihal is double, with a companion, 2.5 seconds of arc apart.

See also: From Ar. an-nihal (النهال) “the thirsty camels, drinking camels,” plural form of an-nâhil (الناهل).

A → cardinal number between → eight and → ten.

Etymology (EN): M.E., from O.E. nigen, nigan, nigon, akin to M.Du. neghen, Du. negen, O.H.G. niun, Ger. neun, Goth. niun “nine,” Pers. noh, as below; from PIE *newn “nine.”

Etymology (PE): Noh, from Mid.Pers. nô; Av. nava; cognate with Skt. nava-; Gk. ennea; L. novem.

A → cardinal number between → eight and → ten.

Etymology (EN): M.E., from O.E. nigen, nigan, nigon, akin to M.Du. neghen, Du. negen, O.H.G. niun, Ger. neun, Goth. niun “nine,” Pers. noh, as below; from PIE *newn “nine.”

Etymology (PE): Noh, from Mid.Pers. nô; Av. nava; cognate with Skt. nava-; Gk. ennea; L. novem.

The small conical projection in the centre of the areola of each breast, which in women contains the outlet of the milk ducts. Also called: mamilla, papilla or teat (TheFreeDictionary).

Etymology (EN): M.E. nyppell, neple, “teat,” from neble, diminutive of neb “bill, beak,” + -le, → -ule.

Etymology (PE): Mamak, diminutive of mame “breast” in child language, maybe related to mâm, → mother.

The small conical projection in the centre of the areola of each breast, which in women contains the outlet of the milk ducts. Also called: mamilla, papilla or teat (TheFreeDictionary).

Etymology (EN): M.E. nyppell, neple, “teat,” from neble, diminutive of neb “bill, beak,” + -le, → -ule.

Etymology (PE): Mamak, diminutive of mame “breast” in child language, maybe related to mâm, → mother.

Gaseous chemical element; symbol N. Nitrogen is the most abundant constituent of dry air. It comprises 78.09% (by volume). → Atomic number 7; → atomic weight 14.0067; → melting point -209.86°C; → boiling point -195.8°C. Nitrogen is a colorless, odorless, tasteless diatomic gas. It was discovered by the Scottish physician and chemist Daniel Rutherford in 1772.

Etymology (EN): From Fr. nitrogène, coined 1790 by Fr. chemist Jean Antoine Chaptal (1756-1832), from combining form of Gk. nitron “sodium carbonate” + Fr. gène “producing.”

Etymology (PE): Azot, loan from Fr. azote, from Gk. azotos “lifeless,” from negation prefix → a- + zotos “vital.”

Gaseous chemical element; symbol N. Nitrogen is the most abundant constituent of dry air. It comprises 78.09% (by volume). → Atomic number 7; → atomic weight 14.0067; → melting point -209.86°C; → boiling point -195.8°C. Nitrogen is a colorless, odorless, tasteless diatomic gas. It was discovered by the Scottish physician and chemist Daniel Rutherford in 1772.

Etymology (EN): From Fr. nitrogène, coined 1790 by Fr. chemist Jean Antoine Chaptal (1756-1832), from combining form of Gk. nitron “sodium carbonate” + Fr. gène “producing.”

Etymology (PE): Azot, loan from Fr. azote, from Gk. azotos “lifeless,” from negation prefix → a- + zotos “vital.”

Science of → snow.

Etymology (EN): From Fr. nivologie, from niveus “snow; snowy,” → snow, + -logie, → -logy.

Etymology (PE): Barfšenâsi, frp barf, → snow,

• -šenâsi, → -logy.

Science of → snow.

Etymology (EN): From Fr. nivologie, from niveus “snow; snowy,” → snow, + -logie, → -logy.

Etymology (PE): Barfšenâsi, frp barf, → snow,

• -šenâsi, → -logy.

The second satellite of → Pluto discovered in 2005 by astronomers using the → Hubble Space Telescope images. It has an estimated diameter of between 46 and 137 km and an orbital period of 24.9 days. Also called Pluto II (P2).

See also: Nix, from Nyx in Gk. mythology the goddess of darkness and night. The conversion of “i” into “y” was to avoid conflict with the asteroid 3908 Nyx.

The second satellite of → Pluto discovered in 2005 by astronomers using the → Hubble Space Telescope images. It has an estimated diameter of between 46 and 137 km and an orbital period of 24.9 days. Also called Pluto II (P2).

See also: Nix, from Nyx in Gk. mythology the goddess of darkness and night. The conversion of “i” into “y” was to avoid conflict with the asteroid 3908 Nyx.