extension

noun ex·ten·sion \ ik-ˈsten(t)-shən \
Updated on: 16 Nov 2017

Definition of extension

1 a : the action of extending : state of being extended
b : an enlargement in scope or operation
  • tools are extensions of human hands
2 a : the total range over which something extends : compass
b : denotation 4
3 a : the stretching of a fractured or dislocated limb so as to restore it to its natural position
b : an unbending movement around a joint in a limb (such as the knee or elbow) that increases the angle between the bones of the limb at the joint — compare flexion 4a
4 : a property whereby something occupies space
5 : an increase in length of time; specifically : an increase in time allowed under agreement or concession
6 : a program that geographically extends the educational resources of an institution by special arrangements (such as correspondence courses) to persons otherwise unable to take advantage of such resources
7 a : a part constituting an addition
b : a section or line segment forming an additional length
c : an extra telephone connected to the principal line
d : a length of natural or synthetic hair that is worn attached to one's natural hair
e : a series of usually three or four characters following a dot at the end of the name of a computer file that specifies the file's format or purpose
8 : a mathematical set (such as a field or group) that includes a given and similar set as a subset

Examples of extension in a Sentence

  1. extension of the patient's life

  2. He's asking for a contract extension.

  3. Make sure that the muscles get the proper amount of extension.

  4. I missed the deadline but was granted an extension.

Recent Examples of extension from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'extension.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of extension

Middle English, from Late Latin extension-, extensio, from Latin extendere



EXTENSION Defined for Kids

extension

noun ex·ten·sion \ ik-ˈsten-shən \

Definition of extension for Students

1 : the act of making something longer or greater
  • extension of the sail
2 : an increase in length or time
3 : a part forming an addition or enlargement

Medical Dictionary

extension

noun ex·ten·sion \ ik-ˈsten-chən \

medical Definition of extension

1 : the stretching of a fractured or dislocated limb so as to restore it to its natural position
2 : an unbending movement around a joint in a limb (as the knee or elbow) that increases the angle between the bones of the limb at the joint — compare flexion 1

Law Dictionary

extension

noun ex·ten·sion

legal Definition of extension

: an increase in length of time; specifically : an increase in the time allowed under an agreement


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