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

1) The statement or discussion of the first principles of any science or art (1913 Webster).
2) Logic: The doctrine of the elementary requisites of mere thought (Sir W. Hamilton; 1913 Webster).

→ stoichiometry, → -logy.

A kind of → deductive reasoning whereby from two initial → propositions (two → premises) a third related proposition (→ conclusion) is derived. The typical form of a → categorical syllogism is "A is B;" "C is A;" "Therefore, C is B." For example, "All humans are mortal." "John is human." "Therefore, John is mortal." "Mortal" (B) is called the → major term; it occurs in the first premise and is the → predicate of the conclusion. "John" (C), the subject of the conclusion, is called the → minor term. "Human," which is common to both premises and is excluded from the conclusion, is called the → middle term. See also → Aristotelian forms. Syllogism is purely formal. It does not enrich knowledge, but gives a new presentation to what is already known. It is also possible to have a logically valid syllogism based on → absurd premises. For example, "All cats are mammals." "All cats are animals." "Therefore, all animals are mammals." Syllogism, representing the earliest branch of → formal logic, was developed in its original form by Aristotle in his Organon (Prior Analytics) about 350 BC.
See also: → bivalent logic, → polyvalent logic, → symbolic logic, → propositional logic, → first-order logic, → predicate logic, → syllogistic; → fuzzy logic.

M.E. silogisme, from O.Fr. silogisme, from L. syllogismus, from Gk. syllogismos "a syllogism," originally "inference, conclusion; computation, calculation," from syllogizesthai "bring together before the mind, compute, conclude," from assimilated form of → syn- "together" + logizesthai "to reason, to count," from logos "a reckoning, reason," → logic.

Bâhamšomârik, literally "reckoning together," from bâham "together," from bâ "with," → hypo-, + ham, → syn-, + šomâr present stem of šomârdan "to reckon, calculate, enumerate, account for," → count, + suffix -i.

1a) Of or pertaining to a → syllogism.
1b) Like or consisting of syllogisms.
2a) The part of logic that deals with syllogisms.
2b) Syllogistic reasoning (Dictionary.com).

→ syllogism; → -ic.

A modern development of → formal logic based on a system of → symbols and → axiomatics in accordance with precise rules. It uses a formalized → artificial language to avoid the ambiguities and logical inadequacies of → natural languages. Symbolic logics are → polyvalent when they admit → truth values other than → true and → false.

→ symbolic; → logic.

1) Needless repetition of an idea, especially in words other than those of the immediate context, without imparting additional force or clearness, as in "lifeless dead."
2) A → proposition that is → always  → true. On a → truth table a tautology is a → sentence that is true for every possible → truth value of its constituent parts.

L.L. tautologia "representation of the same thing in other words," from Gk. tautologia, from tautologos "repeating what has been said," from tauto "the same" (contraction of to auto "the same," from to "the" + → auto + -logos "saying," related to legein "to say," → -logy.

Hamân "same" (Mid.Pers. ham "same; also; together," → com-) + ân "that."

The use of scientific knowledge for the creation and development of devices, machines, and techniques to achieve a commercial, industrial, or scientific objective.

From Gk. tekhnologia "systematic treatment of an art, craft, or technique," originally referring to grammar, from tekhno-, from tekhne, → technique, + → -logy.

1) The system of terms belonging to a particular science, art, specialized subject, or social group. Terminology is the way of naming concepts, which generally precede the corresponding terms. See also → lexicology.
2) The theory or science dealing with the relations between → terms and → concepts.

A hybrid word coined first in Fr., before 1764, by Yves Marie André (1675-1764), a Jesuit mathematician and philosopher, from termin, from L. terminus, → term, + epenthetic vowel -o- + Gk. -logia, → -logy. Recoined or borrowed in Ger. Terminologie in 1786, by C.G. Schütz of Jena; first appeared in E. in 1801.

From tarm, → term, + -šenâsi, → -logy.

A person versed in theology, especially Christian theology (Dictionary.com)

→ theology.

The field of study and analysis that treats of → God and of God's attributes and relations to the universe; study of divine things or religious truth; divinity (Dictionary.com).

→ theism; → -logy.

Of or relating to → topology.

→ topology; → -ic; → -al

In → cosmological models, a stable configuration of → matter formed when the → early Universe underwent → phase transitions during which fundamental symmetries were broken. There are a number of possible types of defects, such as domain walls, → cosmic strings, → magnetic monopoles, and → texture s. Same as → cosmic defect.

→ topological; → defect.

A set X together with a collection of open subsets T that satisfies the three following conditions: 1) The empty set Ø and X are in T. 2) The intersection of a finite number of sets in T is also in T. 3) The union of an arbitrary number of sets in T is also in T.

→ topological; → space.

The study of the properties of geometric figures that remain invariant under certain transformations, as bending or stretching. A circle is topologically equivalent to an ellipse (into which it can be deformed by stretching) and a sphere is equivalent to an ellipsoid.

From topo- combining form of Gk. topos "place" + → -logy.

Topošenâsi, from topo-, loan from Gk., as above, + šenâsi→ -logy.

In Kantian epistemology, a pure logic which contains solely the rules of the pure thought of an object, excluding any mode of knowledge with empirical content. Whereas general logic is not concerned with the origin of our cognitions, transcendental logic would contain rules for the use of → a priori cognitions.

→ transcendental; → logic.

A term that describes the collective efforts of those who study → unidentified flying object (UFO) reports.

Ufo, from → unidentified flying object; → -logy.

A catalog of → reflection nebulae containing 158 objects. The catalog gives information for all BD and CD stars north of δ = -33 deg which are surrounded by reflection nebulosity visible on both the blue and red prints of the → Palomar Observatory Sky Survey .

van den Bergh, S., 1966, AJ, 71, 990; → catalog

A stellar catalog which is the world's principal database of astrometric → double star information. It is maintained by the United States Naval Observatory. The WDS Catalog contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of 142552 systems (as of Feb 27 2018).

Washington, referring to the location of the United States Naval Observatory in Northwest Washington, D.C; → double; → star; → catalog.