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

The doctrine that certain vast geological changes in the Earth's history were caused by sudden, short-lived, violent events rather than gradual evolutionary processes. Catastrophism explains the differences in → fossil forms encountered in successive → stratigraphic levels. This doctrine is associated with the French naturalist Baron Georges Cuvier (1769-1832). Catastrohism is contrasted to the → uniformitarianism.

→ catastrophe; → -ism.

1) Unambiguously explicit and direct, without exceptions or conditions.
2) Relating to or included in a → category.
3) Logic: Of a → proposition (→ syllogism), consisting of a → subject and a → predicate, each of which denotes a class, and having one of the → Aristotelian forms.

→ category; → -ic; → -al.

In a → syllogism, a → proposition or statement that deals with inclusion or exclusion of members of → subject classes in → predicate classes. Categorical propositions are of four basic forms, see → Aristotelian form.

→ categorical; → proposition.

A standard → syllogism that consists of three → categorical propositions in which there are three terms, and each term appears exactly twice. The three terms in a standard categorical syllogism are the → major term, → mino term, and → middle term.

→ categorical; → syllogism.

To place in a → category or class.

→ category; → -ize.

1) A group of things that are similar in some way.
2a) Philo.: In Aristotelian logic, any of the ten different ways (substance, quantity, quality, relation, place, time, position, possession, doing, and undergoing) in which the subject of a proposition may relate to its predicate. For example, the proposition "All men are mortal" belongs to the Category of Quality since it tells us what "all men" are like, namely mortal.
2b) Philo.: In Kant's system, any of the twelve (four groups of three each) pure concepts of the understanding that constitute necessary conditions of experience and correspond with the classes of judgements treated in formal logic. According to Kant, the categories are results of the mind's activity, and are distinguished from sensation. The categories have, furthermore, like space and time relations, a peculiar universality. They are, in other words, a priori.
3) Math.: An entity consisting of a class of objects and a class of → morphisms between those objects that satisfy certain properties.

M.Fr. catégorie, from L.L. categoria, from Gk. kategoria, from kategorein "to speak against; to accuse, assert, predicate," from kata "down, against, back," → cata-, + agorein "to speak before public assembly," from agora "marketplace, public square" (from ageirein "to gather"); cognate with L. grex, gregis "herd, troop, crowd;" Skt. gramah- "heap, crowd, community;" Old Icelandic kremja "to squeeze;" O.E. crammian "to cram;" Latvian  gùrste "bundle of flask;" Polish garnac "to gather;" Russ. gorst' "cupped hand;" cf. Pers. gor-, gal-, etc., as below; PIE base *ger- "to gather."

Katâgor, from katâ-, → cata-, + gor- "to gather," ultimately from PIE *ger-, as above. We put forward that the following Iranian words derive from the above PIE base *ger- "to gather":
goruh "crowd, troop, band;"
gallé (conversion of r to l) "herd, flock;"
jarra (Laki) "group; stick bundle;"
gerd in gerd âvardan "to collect, bring together" probably not related to gerd "round, circular;"
xalam (štiyâni) "herd, flock;"
xelima (Qâyeni) "herd;"
korand, korang "a ring made by hunters or troops;"
korka (Laki) "bundle of harvested ears of wheat;"
gola, golé "bundle of hair; bunch"
gola-gâh "place of gathering;"
gurâb "market place in a village, agora;"
There are dozens of villages all-over Iran named Gorâb, Gurâb, Gela, Gola, Gala and their combinations with other words (e.g. Galadeh, Galazan, Galavand) that probably refer to places of gathering.
One can also mention village names such as Agora, Gore, Gere(kalâ), Garaku, Oger, and so on in Mâzandarân;
Khotanese (prefixed ham-) gris "to assemble."

A theory that deals with the concept of → category and generalizes the → set theory.

→ category; → theory.

A negatively charged electrode that is the source of electrons in an electrical device.

Gk. kathodos "descent, a way down," from kata- "down" + hodos "way, path."

A kind of ray generated at the cathode in a vacuum tube, by the electrical discharge.

→ cathode; →ray.

Same as → universal astrolabe.

Catholic, M.E., from Fr. catholique, from Church Latin catholicus "universal, general," from Gk. katholikos, from phrase kath' holou "on the whole, in general," from kata "about," → cata-, + genitive of holos "whole," → holo-; → astrolabe.

Ostorlâb, → astrolabe; hargâni, → universal.

Chemistry: A → positively charged → ion that is attracted to the → cathode in electrolysis. Any positively charged atom or group of atoms (opposed to → anion).

From cat-, → cathod, + → ion.

Light that is reflected from a curved surface mirror.

→ catoprtics; → light.

An optical system in which the light is reflected only.

→ catoprtics; → system.

The area of → optics which treats of the laws and properties of light reflected from reflective surfaces.

From Gk. katoptrikos, from katoptron "mirror" (from kat-, → cata-, + op- "to see," → optics, + -tron suffix of instruments) + -ikos, → -ics.

Bâztâbik, from bâztâb, → reflection, + -ik, → -ics.

Domesticated quadrupeds held on a farm, especially oxen, bulls, and cows.

M.E. catel, from M.Fr. catel "property" (O.Fr. chatel), from M.L. capitale "property, stock," from L. capitalis "principal, chief," literally "of the head," from caput, → head.

Dâm, originally "nonferocious animal," especially "herbivorous quadrupeds such as cows, sheep, etc.;" Mid.Pers. dâm "creature, creation;" O.Pers. dā- "to put, make, create;" Av. dā- "to place, put, create," dāmay- "creation; creating; creator," dāmi.dāt- "creating the creation;" cf. Skt. dhā- "to put, to place;" Gk. tithemi "to put, to place;" L. facere "to do;" O.H.G. tuon; E. to do.

A relationship between the → refractive index (n) and the wavelength of light (λ) passing through a medium. It is commonly stated in the following form: n = A + B/λ² + C/λ⁴, where A, B, and C are constants characterizing the medium. The two-component Cauchy equation is n = A + B/λ², from which the dispersion becomes dn/dλ = -2B/λ³ showing that dispersion varies approximately as the inverse cube of the wavelength. The dispersion at 4000 A will be about 8 times as large as at 8000 Å.

Named after Augustin Louis Cauchy (1789-1857), French mathematician and physicist who found the first equation of dispersion in 1836; → equation.

If f(x) and φ(x) are two → continuous functions on the → interval [a,b] and → differentiable within it, and φ'(x) does not vanish anywhere inside the interval, there will be found, in [a,b], some point x = c, such that [f(b) - f(a)] / [φ(b) - φ(a)] = f'(c) / φ'(c).

→ Cauchy's equation; → theorem.

Of, involving, or constituting a cause; indicative of or expressing a cause.

Adj. from → cause.

In → special relativity, the causal relationship between → events involving a → light cone.

→ causal; → structure.

The relationship between causes and effects

Causality, from → causal + -ity.

Bonârmandi, from bonâr→ cause + -mand suffix denoting relation, affinity + -i noun forming suffix.