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

A flow whose volume or density does not change under pressure, and therefore its density is a constant. In other words, an ideal flow in which the → divergence of velocity is zero. → compressible flow.

→ incompressible, from → in "not" + → compressible; → flow.

1) Lack of consistency or agreement; incompatibility; an inconsistent feature or quality.
2) Logic: The property of being inconsistent; a self-contradictory proposition (TheFreeDictionary.com).

→ in-; → consistency.

1) Lacking in consistency, agreement, or compatibility; at variance.
2) Containing contradictory elements.
4) Maths: (of two or more equations) not having one common set of values of the variables: x + 2y = 5 and x + 2y = 6 are inconsistent
5) Logic: (of a set of propositions) Enabling an explicit contradiction to be validly derived (TheFreeDictionary.com).

→ in-; → consistent.

1) To make or become greater, in number, size, degree, etc..
2) The act of increasing. The amount by which something increases.

M.E., from O.Fr. encreiss-, pr.p. stem of encreistre, from L. increscere "to increase, to grow upon," from → in- "in" + crescere "to grow," → crescent.

Afzudan, from Mid.Pers. abzudan "to increase, grow," O.Pers. abijav- "to increase, add to, promote," from abi-, aiby- "in addition to; to; against" + root jav- "press forward," Av. gav- "to hasten, drive," Sk. jav- "to press forward, impel quickly, excite," javate "hastens."

The amount by which a varying quantity increases between two of its stages. In → calculus, the Greek letter Δ (delta) is used to denote an increment; e.g. Δx is an increment of x, contrasted to → decrement.

Increment, from L. incrementum "growth, increase," from stem of increscere "to grow in or upon" from → in- "in" + crescere "to grow."

Fazâyé, from fazâ shortened present stem of afzudan "to add, increase" (Mid.Pers. abzudan "to increase, grow;" O.Pers. abijav- "to increase, add to, promote," from abi-, aiby- "in addition to; to; against" + root jav- "press forward;" Av. gav- "to hasten, drive;" Skt. jav- "to press forward, impel quickly, excite," javate "hastens") + -y- euphonic infix + -é noun/nuance suffix.

Not → definite; without fixed or specified limit.

From → in- "not, without" + → definite.

Math.: An integral without upper and lower limits. The general antiderivative of a function. → definite integral.

→ definite; → integral.

Not dependent.

From negation prefix → in- + → dependent.

Statistics: Two events if the occurrence of one of them gives no → information about whether or not the other event will occur; these events have no influence on each other.

→ independent; → event.

Statistics: Two random variables X and Y if and only if the value of X has no influence on the value of Y and vice versa.

→ dependent; → random; → variable.

Math.: A variable whose value determines the value of other variables. For example, x, in the expression y = f(x), is the independent variable. See also → dependent variable.

→ independent; → variable.

Philosophy: The doctrine that there are events which do not correspond with determinism and therefore are uncaused in some sense.
Quantum physics: The claim that the most basic constituents of matter behave indeterministically, in accordance with such properties as the → uncertainty principle.

→ in-; → determinism.

Nâtarmbâvari, nâtarmvari, from nâ- negation prefix + (â)tarmbâvari, (â)tarmvari, → determinism.

1) Math.: A number or symbol, often written as a → subscript or → superscript to a mathematical expression, that indicates an operation to be performed, an ordering relation, or a use of the associated expression.
2) Physics: A measure of a particular property; e.g. → adiabatic index; → color index; → index of refraction.
3) In some → astrolabes, the → rule.
4) A sequential arrangement of items, especially in alphabetical or numerical order. → Index Catalogue.

Index, from L. index "forefinger, pointer, sign," literally "anything which points out," from indicare "point out, show," from in- "in" + dicare "to proclaim," from stem of dicere "to speak, to say;" PIE base *deik- "to point out" (cf. Av. daēs- " to show;" Skt. dic- "to point out, show;" Gk. deiknynai "to prove;" O.H.G. zeigon; Ger. zeigen "to show;" O.E. teon "to accuse," tæcan "to teach").

1) Dišan, from diš-, simple aorist of Av. daēs- "to show," as above, + suffix -an.
2) Fehrest, from Mid.Pers. payrâstag "arranged," from payrâstan "to arrange; to adorn" (Mod.Pers. pirâstan); Proto-Ir. *pati-rāsta-, from *pati "to, at, for, in" (cf. Mid.Pers. pad "to, at, for, in;" Mod.Pers. be, beh; Old.Pers. paity; Av. paiti "to, toward, in, at;" Skt. práti; Gk. poti) + *rād- "to direct, arrange" (cf. Mod.Pers. raj "line, row," variants raž, rak, râk, rezg (Lori), ris, risé, radé, rasté, râsté, related to râst "right, true; just, upright, straight;" Mid.Pers. râst "true, straight, direct;" Sogdian rəšt "right;" O.Pers. rāsta- "straight, true," rās- "to be right, straight, true;" Av. rāz- "to direct, put in line, set," razan- "order;" cf. Skt. raj- "to direct, stretch," rjuyant- "walking straight;" Gk. orektos "stretched out;" L. regere "to lead straight, guide, rule," p.p. rectus "right, straight;" PIE base *reg- "move in a straight line," hence, "to direct, rule").

Either of two catalogues of non-stellar objects, which serve as supplements to the → New General Catalogue.

→ index; → catalog

Same as → refractive index.

→ index; → refraction.

The → numeral system consisting of the numerals 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 which evolved into the system we use today. The Indian numerals was a place-value or positional system. The Indians were the first to develop a base 10 positional system. Same as → Hindu-Arabic numeral system.

Indian, from India, → Indus; → numeral; → system.

A color between blue and violet.

From Sp. indico, Portuguese endego, and Du. (via Portuguese) indigo, from L. indicum "indigo," from Gk. indikon "blue dye from India," literally "Indian (substance)," neuter of indikos "Indian," → Indus.

Nil "indigo color; the indigo plant;" Mid.Pers. nil; cf. Skt. nīlī, nīlā "the indigo plant; indigo color."

Not in a direct course, path, action, or procedure.

→ in-; → direct.

A word or group of words representing the person or thing with reference to which the action of a verb is performed. In English generally coming between the verb and the direct object and paraphrasable as the object of a preposition, usually to or for, following the direct object, as the boy in He gave the boy a book (Dictionary.com).

→ indirect; → object.

1a) A single human being, as distinguished from a group (Dictionary.com).
1b) A distinct, indivisible entity; a single thing, being, instance, or item (Dictionary.com).
1c) Logic: An → object or element taken as the → subject of the → predicates of → first-order logic.
2) Of, pertaining to, or characteristic of a particular person or thing. → individual constant, → individual variable.

M.E., from M.L. individualis, from L. individuus "indivisible," from → in- "not, opposite of" + dividuus "divisible," from dividere, → divide.

Takâl, from tak, → single, + suffix -âl, → -al; takâli with adj. suffix -i.