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

1) The act or fact of igniting; state of being ignited.
2) The process of setting something on fire.

Verbal noun of → ignite.

The minimum temperature to which a fuel must be heated in order to initiate self sustained combustion independent of another heat source.

→ ignition; → temperature.

General: An act or instance of illuminating. The fact or condition of being illuminated.

Illumination, from O.Fr. illumination, from L. illuminationem (nom. illuminatio), from illuminare "to throw into light," from → in- "in" + lumen "light," cognate with Pers. rowšan, as below.

Rowšanâyi, noun of quality and state from rowšan "bright, clear," related to ruz "day," foruq "light," and afruxtan "to light, kindle," rowzané "window, aperture;" Mid.Pers. rôšn "light; bright, luminous," rôc "day," rocânak "window;" O.Pers. raucah-, Av. raocana- "bright, shining, radiant," raocah- "light, luminous; daylight;" akin to Skt. rocaná- "bright, shining," roka- "brightness, light;" Gk. leukos "white, clear;" L. lux "light," also lumen "light, window," luna "Moon;" E. light; Ger. Licht; Fr. lumière; PIE base *leuk- "light, brightness."

1) A false sense impression of something actually present.
2) Something that produces a false or misleading impression of reality. → optical illusion.
3) An instance of being deceived.

From O.Fr. illusion "a mocking," from L. illusionem (nom. illusio) "a mocking, irony," from illudere "to mock at," literally "to play with," from in- "at" + ludere "to play," from ludus "a game, play;" PIE base *leid- "to play, jest."

Safmân, literally "wrong thought, ~ idea," from saf "wrong" (Tâleši), → false, + mân "thought," → idea.

The meeting of light rays emanating from an object after crossing an optical system.

→ image; → formation.

The separation between two detached but adjacent points in an image.

→ image; → resolution.

The process by virtue of which the original image can be created by removing the blurring and the noise that occur during image formation.

→ image; → restoration.

1) The faculty of imagining, or of forming mental images or concepts of what is not actually present to the senses.
2) The action or process of forming such images or concepts (Dictionary.com).

→ imagine; → -tion.

The disappearance of a star, planet, moon, or other body at the beginning of an → occultation or → eclipse. Also called → ingress.

→ immerge.

An → atmospheric escape mechanism that occurs where atmospheric gases are expelled en masse as a result of large body impacts, such as the cumulative effect of asteroids hits (see, e.g., Catling, D. C. and Kasting, J. F., 2017, Escape of Atmospheres to Space, pp. 129-167. Cambridge University Press).

→ impact; → erosion.

The loss of orbital electrons by an atom of a crystal lattice which has undergone a high-energy collision.

→ impact; → ionization.

A fault, flaw, or undesirable feature; the state or condition of being imperfect.

→ in-; → perfection.

1) General: Something implied; the act of implying.
2) A statement that follows from other given statements. For ex., an implication of x = -1 is that x² = 1.
3) A proposition found from two given propositions by connecting them in the form "If ..., then ...". The first statement is the antecedent (or hypothesis) and the second the consequent (or conclusion).

From L. implicationem "interweaving, entanglement," from implicatus, p.p. of implicare "involve, entangle, connect closely," from → in- "in" + plicare "to fold," → explain.

Dartâheš, verbal noun of dartâhidan "to imply," from dar-, → in- + tâhidan "to fold, ply," → explain.

A function which contains two or more variables that are not independent of each other. An implicit function of x and y is one of the form f(x,y) = 0, e.g., 4x + y² - 9 = 0. See also → explicit function.

→ implicit; → function.

A violent inward collapse; the act of imploding; opposed to → explosion.

Verbal noun of → implode.

1) The laying on of something as a burden or obligation.
2) Something imposed, as a burden or duty; an unusual or extraordinarily burdensome requirement or task.
3) The act of imposing by or as if by authority (Dictionary.com).

→ impose; → -tion.

The quality of lacking → precision.

From im-, variant of → in- + → precision.

1) A strong effect produced on the intellect, feelings, conscience, etc.
2) The first and immediate effect of an experience or perception upon the mind (dictionary.com).

→ press + -ion variant of → -tion.

Capable of being impressed; easily impressed.

→ impress; → -able.

1) A style of painting developed in the last third of the 19th century, characterized chiefly by short brush strokes of bright colors in immediate juxtaposition to represent the effect of light on objects.
2) A manner of painting in which the forms, colors, or tones of an object are lightly and rapidly indicated.
3) A manner of sculpture in which volumes are partially modeled and surfaces roughened to reflect light unevenly (Dictionary.com).

→ impression; → -ism.