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Related to combination: Combination reaction


in business: see trusttrust,
in law, arrangement whereby property legally owned by one person is administered for the benefit of another. Three parties are ordinarily needed for the relation to arise: the settlor, who bequeaths or deeds the property for another's benefit; the trustee, in whose hands
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The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(in Russian, kombinatsiia). (1) An interdependent union, connection, or arrangement of several objects or component parts (elements) of a single object.

(2) A set of procedures for carrying out a complex plan, such as a chess combination.

(3) A contrivance, trick, or subterfuge; a deliberate maneuver to achieve a mercenary or other improper goal (commercial combination; political combination).

(4) An item of women’s underclothing (a slip).



in mathematics. Combinations of n elements taken k at a time are sets that contain k of the n elements and that differ from each other in at least one element. The number of combinations of n elements, k at a time, is denoted by Combination, C (n, k), or Combination and is equal to n!/k!(n - k)! (seeCOMBINATORICS).

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


A selection of one or more of the elements of a given set without regard to order.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


a. the set of numbers that opens a combination lock
b. the mechanism of this type of lock
2. Brit a motorcycle with a sidecar attached
3. Maths
a. an arrangement of the numbers, terms, etc., of a set into specified groups without regard to order in the group
b. a group formed in this way. The number of combinations of n objects taken r at a time is n!/[(n -- r)!r!]. Symbol: nCr
4. the chemical reaction of two or more compounds, usually to form one other compound
5. Chess a tactical manoeuvre involving a sequence of moves and more than one piece
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005


A set containing a certain number of objects selected from another set.

The number of combinations of r objects chosen from a set of n is

n C r = n! / ((n-r)! r!)

where "n C r" is normally with n and r as subscripts or as n above r in parentheses.

See also permutation.


In the theory of combinators, a combination denotes an expression in which function application is the only operation.
This article is provided by FOLDOC - Free Online Dictionary of Computing (
References in periodicals archive ?
In July this year, the fair trade regulator had invited comments for the amendments in the Competition Commission of India (Procedure in regard to the transaction of business relating to combinations) Regulations.
"We expect several of these combinations, or more, will work much better than existing antibiotics."
Now, a team of UCLA biologists has discovered thousands of four- and five-drug combinations of antibiotics that are more effective at killing harmful bacteria than the prevailing views suggested.
Says the report, "Drug-device combination is defined as the combination of drugs and medical devices that can be chemically or physically united or co-packaged as separate, cross-labeled products.
Information released to BBC Wales following a Freedom of Information (FOI) request and seen by the Press Association revealed that other combinations such as JE** HAD and *J11 HAD were also banned.
Currently, there are three common types of LTC combination products in the U.S.
The NDA for the closed triple combination therapy will comprise data now in hand from the closed triple combination therapy development programme, as well as data from studies with FF, UMEC and VI either alone or in combination.
U.S.$20,000,000 Class 3 Combination Notes (composed of components representing U.S.$16,000,000 of Class C Notes and U.S.$4,000,000 of subordinated notes ( the "Class 3 Combination Notes Components", and together with the Class 1 Combination Notes Components and Class 2 Combination Notes Components, the "Underlying Components") due 2028 (the "Class 3 Combination Notes", and together with the Class 1 Combination Notes and the Class 2 Combination Notes, the "Combination Notes"), Assigned A2 (sf)
Researchers working with a large US group of HIV-positive adults conducted this new study with three major goals: (1) to see whether people with HIV changed a first or second antiretroviral combination less in the more recent years of a 15-year period, (2) to see whether rates of HIV control (an undetectable viral load) changed over those 15 years, and (3) to identify factors that made changing to a new antiretroviral combination more likely or reaching an undetectable viral load less likely.
This means that a combination of drugs, acting upon as many pathologic mechanisms as possible, is necessary for optimal management of the syndrome.