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1. The act of extending or the condition of being extended: the extension of the subway into the suburbs.
2. The amount, degree, or range to which something extends or can extend: The wire has an extension of 50 feet.
a. The act of straightening or extending a limb.
b. The position assumed by an extended limb.
4. A length of human or synthetic hair attached to the scalp or to strands of hair close to the scalp to add volume, length, or color.
5. Medicine The application of traction to a fractured or dislocated limb to restore the normal position.
a. An addition that increases the area, influence, operation, or contents of something: an extension for the vacuum cleaner; built a new extension onto the hospital wing.
b. An additional telephone connected to a main line.
a. An allowance of extra time, as for the repayment of a debt.
b. The period of this extra time: three months' extension on the loan.
8. The property of an object by which it occupies space.
a. A program in a university, college, or school offering academic instruction to nontraditional students, such as working adults, who cannot attend classes at the usual place and time.
b. A publicly funded program offering such instruction along with information on agriculture, home economics, and business.
10. Computers A set of characters that follow a filename and are separated from it by a period, used to identify the kind of file: In most operating systems, filenames having the extension .EXE are executable files.
11. Logic The class of objects designated by a specific term or concept; denotation.
12. Mathematics A set that includes a given and similar set as a subset.

[Middle English extensioun, from Old French extension, from Latin extēnsiō, extēnsiōn-, from extēnsus, past participle of extendere, to extend; see extend.]

ex·ten′sion·al adj.


1. (Logic) relating to or characterized by extension
2. (Logic) logic explicable solely in terms of extensions; ignoring differences of meaning that do not affect the extension. See also extensionality, substitutivity, transparent context
exˈtensionally adv
exˈtensionalism n
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.extensional - defining a word by listing the class of entities to which the word correctly applies
logic - the branch of philosophy that analyzes inference
denotative, denotive - having the power of explicitly denoting or designating or naming
References in periodicals archive ?
It has completed an infill and extensional drilling programme at Bagassi South, which resulted in a significant grade increase of approximately 37% in the Mineral Resource Estimate (MRE).
According to the plate characteristics and the classification of sedimentary basins [21], the oil shale-bearing basins in China can be divided into four types: extensional basins, flexural basins, intra-plate basins and strike-slip basins.
Among their topics are semantic connotations and symbolic reasons behind burial and tomb positions in Igbo land, the optimal utilization of indigenous languages: an imperative for attaining Millennium Development Goals, human development disorders and human communication: towards explicating the lexicon of the discourse, the treatment of extensional suffixes in Igbo lexicography, and the post-lexical deletion of r and y in YorubC.
It is therefore cruicial to understand the rate and temperature-dependent extensional properties of polymers to predict their behavior in processing operations.
3) Kelley, the chief consultant in Clinical Psychology and assistant consultant in Psychiatry to the European Theater of Operations (and the chief psychiatrist in charge of the prisoners at Nuremberg), described how GS was used to treat military posttraumatic stress in "The Use of General Semantics and Korzybskian Principles as an Extensional Method of Group Psychotherapy in Traumatic Neuroses," an article he published in 1951 in The Journal of Nervous and Mental Diseases, (4)
With the same small sample requirements and a wide dynamic range, e-VROC maintains the precision and accuracy of the m-VROC viscometer with one slight twist: the capability of measuring apparent extensional viscosity.
Capable of measuring extensional stress, elongational
The Paleozoic rocks show contractional and extensional structures that can be attributed to deformations during the Chanic, Gondwanan, and Andean orogenic cycles (see Ramos, 1988 and works cited therein).
The funds will be used for activities in connection with resource extensional drilling at Mt Kare Gold/Silver Project PNG, and working capital.
The three-volume set surveys the geology of extensional basins including rifts, passive margins, and inverted extensional basins around the world.
It is extensional shear, which generally has been associated only with twin-screw extruders.