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

The part of the Earth's surface between the tropics of Cancer and Capricorn

→ torrid; → zone.

A surface produced by the revolution of a conic section (such as a circle) around a line lying in its plane, but not cutting the conic. The solid enclosed by such a surface.

From L. torus "a round, swelling protuberance."

Cambar "torus," originally "hoop, circle," from Mid.Pers. cambar "hoop; a ring-shaped headdress," cambar vâcik "playing tambourine."

Constituting or comprising the whole; entire; complete in extent or degree. Related term → general = harvin (هروین).

M.E., from O.Fr. total, from M.L. totalis "entire, total," from L. totus "all, whole, entire," of unknown origin.

Mid.Pers. hamâk, hamâg "total, all," hamâkih "totality," related to Mod.Pers. hamé- "all," variant hami "all the time, always;" Mid.Pers. hamê "all the time, always;" Av. hama- "any" (cf. Skt. sama-"any, every, whichever;" Gk. amo-then "whichever;" Goth. sums "any;" O.N. sumr "any;" O.E. sum "some;" E. some) + suffix -âk.

Same as → elemental abundance.

→ total; → abundance.

An → eclipse in which the whole of the disk of the Sun or Moon is obscured. See also → annular eclipse, → partial eclipse, → totality, → totality path.

→ total; → eclipse.

The sum of all forms of energy involved in a system.

→ total; → energy.

A function whose value is defined for all possible input values.

→ total; → function.

In a → rotating star, the sum of the → gravitational, → centrifugal, and → radiative accelerations. See also → effective gravity.

→ total; → gravity.

A phenomenon occurring when a light ray traveling cross an → interface from a higher → refractive index medium to a lower refractive index medium hits the interface at an angle larger than the → critical angle. In these conditions the light will not pass through to the second → medium at all. Instead, all of it will be reflected back into the first medium.

→ total; → internal; → reflection.

A → lunar eclipse when the entire → Moon passes through the Earth's → umbra. The maximum duration of a total lunar eclipse is 1h 47m. It happens when the Moon crosses the umbra at its → apogee, where it moves the most slowly, and the Earth is at its → aphelion. The longest total lunar eclipse of the 21st century, lasting 1h 42m 59s, occurred on the night of 27 to 28 July 2018 (Europe, Africa, Asia, Australia, and New Zealand). See also → tetrad.

→ total; → lunar; → eclipse.

The sum of → static pressure, → dynamic pressure, and → hydrostatic pressure in the → Bernoulli equation.

→ total, → pressure.

1) Of or relating to a centralized government that does not tolerate parties of differing opinion and that exercises dictatorial control over many aspects of life.
2) Exercising control over the freedom, will, or thought of others; authoritarian; autocratic.
3) An adherent of totalitarianism (Dictionary.com).

From totali-, from → totality + -arian, a suffix forming adjectives or nouns ending in → -ary.

Hamâkigerâyi, from hamâki, → totality, + -gerâ, → ist.

1) The practices and principles of a totalitarian regime.
2) Absolute control by the state or a governing branch of a highly centralized institution (Dictionary.com).

→ totalitarian; → -ism.

The period during a → solar eclipse when the → Sun is completely blocked by the → Moon. Totality for a → lunar eclipse is the period when the Moon is in the complete → shadow of the → Earth. For a solar eclipse totality can last from only several fractions of a second to a theoretical maximum of 7m 31s, depending on the → distance from the Moon to the Earth. For a lunar eclipse totality can last up to 1h 47m, also depending on the distance from the Moon to the Earth and on its → passage through the shadow. See also → totality path.

→ total; → -ity.

Of a → solar eclipse, the path of the → umbra across the → Earth. The totality path is usually about 100 km across, but under the most favorable conditions, when the → Moon is at its nearest → distance to Earth and the Earth is at its farthest distance from the Sun, the umbra can have a diameter of about 270 km.

→ totality; → path.

1a) To put the hand, finger, etc., on or into contact with (something) to feel it.
1b) To come into contact with and perceive (something), as the hand or the like does.
2) The act or fact of touching (Dictionary.com)

M.E. to(u)chen, from O.Fr. tochier "to touch, hit; deal with" from V.L. *toccare "to knock, strike" as a bell.

Basâvidan, ultimately from Proto-Ir. *apa-sau-, from *sau- "to rub;" cf. Sogdian ps'w- "to touch;" Pers. + sâyidan, variants sâbidan, sudan "to bruise, file, touch" pasâvidan "to touch" (Khotanese sauy- "to rub."

A building or structure taller than its diameter and high relative to its surroundings, either separated or forming part of a building.

From M.E. tour, earlier tur, tor, from O.Fr., from L. turris, from Gk. tyrris "tower."

Borj "tower," related to Pers. borz "height, magnitude, greatness," boland "high," bâlâ "up, above, high, elevated, height," Laki dialect berg "hill, mountain;" Mid.Pers. burz "height," buland "high;" O.Pers. baršan- "height;" Av. barəz- "high, mount," barezan- "height;" cf. Skt. bhrant- "high;" L. fortis "strong" (Fr. and E. force); O.E. burg, burh "castle, fortified place," from P.Gmc. *burgs "fortress;" Ger. Burg "castle," Goth. baurgs "city," E. burg, borough, Fr. bourgeois, bourgeoisie, faubourg; PIE base *bhergh- "high;" borj loaned into Ar. from Mid.Pers. as burj.

A telescope, usually of long → focal length, that is situated underneath a tower. Tower telescopes are mainly used for observation of the Sun. See also → solar telescope; → solar tower.

→ tower; → telescope.

An object, often a representation of something, that a child can play with

M.E. toye, of unknown origin.

Bâzicé, from bâzi "game, play;" Mid.Pers. wâzig "play, game;" related to bâzidan "to play," bâxtan "to loose;" cf. Skt. vāja- "contest, war, prize, booty;" + -cé suffix of relation.

A simplified model that succeeds in capturing and furthering our understanding of one particular aspect of a physical situation, but which does not manage to describe all important aspects of that situation (Carl H. Brans).

→ toy; → model.