Definition of "extension"

extension

/ɪkˈstɛnʃən/

noun
countable and uncountable, plural extensions
1. The act of extending; a stretching out; enlargement in length, breadth, or time; an increase
2. The state of being extended
  Quotations
  For station is properly no rest, but one kind of motion, relating unto that which physicians (from Galen) do name extensive or tonical; that is, an extension of the muscles and organs of motion, maintaining the body at length, or in its proper figure.
  1650, Thomas Browne, Pseudodoxia Epidemica: […], 2nd edition, London: […] A[braham] Miller, for Edw[ard] Dod and Nath[aniel] Ekins, […]
3. That property of a body by which it occupies a portion of space (or time, e.g. "spatiotemporal extension")
4. A part of a building that has been extended from the original
5. (semantics) Capacity of a concept or general term to include a greater or smaller number of objects; — correlative of intension.
  Quotations
  Perversely, we love John Wick himself. That lethal, bereaved assassin is a good bad guy for our times, the natural extension of Tony Soprano, Walter White and all the other heroic antiheroes the culture has embraced.
  2023 March 14, Caryn James, “John Wick: Chapter 4: 'Soars above most action films'”, in BBC‎
  In addition to concepts and conceptual senses, Frege holds that there are extensions of concepts. Frege calls an extension of a concept a ‘course of values’. A course of values is determined by the value that the concept has for each of its arguments. Thus, the course of values for the concept __ is a dog records that its value for the argument Zermela is the True and for Socrates is the False, and so on. If two concepts have the same values for every argument, then their courses of values are the same. Thus, courses of values are extensional.
  2011 July 20, Edwin Mares, “Propositional Functions”, in The Stanford Encyclopedia of Philosophy‎, retrieved 2012-07-15
6. (linguistics, semantics) semantic widening, broadening of meaning
7. (banking, finance) A written engagement on the part of a creditor, allowing a debtor further time to pay a debt.
8. (medicine) The operation of stretching a broken bone so as to bring the fragments into the same straight line.
9. (weightlifting) An exercise in which an arm or leg is straightened against resistance.
10. (fencing) A simple offensive action, consisting of extending the weapon arm forward.
11. (telecommunications) A numerical code used to indicate a specific telephone in a telecommunication network.
12. (computing) A file extension.
13. (computing) An optional software component that adds functionality to an application.
14. (logic) The set of tuples of values that, used as arguments, satisfy the predicate.
15. (grammar) A kind of derivative morpheme applied to verbs in Bantu languages.
16. (education) University programs that are targeted at the broader (usually adults) community whose participants are not full-time enrolled students.