extension

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The act of extending or the condition of being extended.
• noun The amount, degree, or range to which something extends or can extend.
• noun The act of straightening or extending a limb.
• noun The position assumed by an extended limb.
• noun 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.
• noun Medicine The application of traction to a fractured or dislocated limb to restore the normal position.
• noun An addition that increases the area, influence, operation, or contents of something.
• noun An additional telephone connected to a main line.
• noun An allowance of extra time, as for the repayment of a debt.
• noun The period of this extra time.
• noun The property of an object by which it occupies space.
• noun 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.
• noun A publicly funded program offering such instruction along with information on agriculture, home economics, and business.
• noun Computers A set of characters that follow a filename and are separated from it by a period, used to identify the kind of file.
• noun Logic The class of objects designated by a specific term or concept; denotation.
• noun Mathematics A set that includes a given and similar set as a subset.

from The Century Dictionary.

• noun The act of extending; a stretching or expanding.
• noun The state of being extended; enlargement; expansion; extent.
• noun In physics and metaphysics, continuous quantity of space; also, that property of a body by which it occupies a portion of space.
• noun The character of having continuous quantity of any kind, as length of time, weight, etc.
• noun In logic, the totality of subjects of which a logical term is predicable.
• noun A grant of further time in which to do something which has been set down for a particular day.
• noun That by which something is extended or enlarged; particularly (in the United States), an addition to a house, usually at the rear, and not so high as the main building: as, a dining-room extension.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act of extending or the state of being extended; a stretching out; enlargement in breadth or continuation of length; increase; augmentation; expansion.
• noun (Physics) That property of a body by which it occupies a portion of space.
• noun Capacity of a concept or general term to include a greater or smaller number of objects; -- correlative of intension.
• noun the class or set of objects to which a term refers; -- contrasted with intension, the logical specification which defines members of a class, being the set of attributes which are necessary and sufficient to recognize an object as a member of the class.
• noun (Surg.) The operation of stretching a broken bone so as to bring the fragments into the same straight line.
• noun (Physiol.) The straightening of a limb, in distinction from flexion.
• noun (Com.) A written engagement on the part of a creditor, allowing a debtor further time to pay a debt.
• noun (Surg.) See under Counter.
• noun a table so constructed as to be readily extended or contracted in length.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The act of extending or the state of being extended; a stretching out; enlargement in breadth or continuation of length; increase; augmentation; expansion.
• noun That property of a body by which it occupies a portion of space (or time, e.g. "spatiotemporal extension")
• noun semantics Capacity of a concept or general term to include a greater or smaller number of objects; — correlative of intension.
• noun banking, finance A written engagement on the part of a creditor, allowing a debtor further time to pay a debt.
• noun medicine The operation of stretching a broken bone so as to bring the fragments into the same straight line.
• noun weightlifting An exercise in which an arm or leg is straightened against resistance.
• noun fencing A simple offensive action, consisting of extending the weapon arm forward.
• noun telecommunications A numerical code used to specify a specific telephone in a telecommunication network.
• noun computing A file extension.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun amount or degree or range to which something extends
• noun an addition to the length of something
• noun a mutually agreed delay in the date set for the completion of a job or payment of a debt
• noun an educational opportunity provided by colleges and universities to people who are not enrolled as regular students