Pronunciation: (ik-sten'shun),[key] —n. 1. an act or instance of extending.
2. the state of being extended.
3. that by which something is extended; an addition: a four-room extension to a house. 4. an additional period of time given one to meet an obligation: My term paper wasn't finished so I asked for an extension. 5. something that can be extended; an extended object: a table with drop-leaf extensions. 6. range of extending; degree of extensiveness; extent: the extension of our knowledge. 7. an additional telephone that operates on the principal line.
8. Com.a written engagement on the part of a creditor, allowing a debtor further time to pay a debt.
9. Physics.that property of a body by which it occupies space.
10. Anat. a. the act of straightening a limb.
b. the position that a limb assumes when it is straightened.
11. Surg.the act of pulling the broken or dislocated part of a limb in a direction from the trunk, in order to bring the ends of the bone into their natural situation.
12. Also called extent.Logic.the class of things to which a term is applicable, as “the class of such beings as Plato and Alexander” to which the term “man” is applicable. Cf. intension (def. 5).
13. Math.a function having a domain that includes the domain of a given function and that has the same value as the given function at each point in the domain of the given function.
14. Manège.the act of bringing or coming into an extended attitude.