Definition of extension
3a : the stretching of a fractured or dislocated limb so as to restore it to its natural positionb : 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 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 (as correspondence courses) to persons otherwise unable to take advantage of such resources
7a : a part constituting an additionb : a section or line segment forming an additional lengthc : an extra telephone connected to the principal lined : a length of natural or synthetic hair that is worn attached to one's natural haire : 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 (as a field or group) that includes a given and similar set as a subset
Examples of extension in a sentence
extension of the patient's life
He's asking for a contract extension.
Make sure that the muscles get the proper amount of extension.
I missed the deadline but was granted an extension.
Origin and Etymology of extension
Middle English, from Late Latin extension-, extensio, from Latin extendere
First Known Use: 15th century
EXTENSION Defined for Kids
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 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
Legal Definition of extension
: an increase in length of time; specifically : an increase in the time allowed under an agreement
Learn More about extension
See words that rhyme with extension Thesaurus: All synonyms and antonyms for extension Spanish Central: Translation of extension Nglish: Translation of extension for Spanish speakers Britannica English: Translation of extension for Arabic speakers Britannica.com: Encyclopedia article about extension
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