Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “extension”

extension

noun uk   /ɪkˈsten.ʃən/ us  

extension noun (REACH)

B2 [C or U] the fact of reaching, stretching, or continuing; the act of adding to something in order to make it bigger or longer: Martin Luther King, Jr, campaigned for the extension of civil rights to (= for them to include) black people. The extension (= increasing) of police powers in the province has been heavily criticized. His report contained serious criticisms of the finance director, and, by extension (= therefore), of the entire board of management. The article is an extension of (= takes further) the ideas Professor Fox developed in an earlier book. I've applied for an extension to my visa (= asked for it to last longer). They are hoping to get an extension of their loan (= to be given a longer period of time in which to pay it back).

extension noun (BUILDING)

[C] UK (US addition) a new part added to a house or other building: We're building an extension to/on our house.

extension noun (PHONE)

B2 [C] any of two or more phones in the same house that share the same number, or any of a number of phones connected to a switchboard in a large building such as an office: We have an extension in our bedroom. When you call, ask for extension 3276.

extension noun (COMPUTER)

[C] the last part of the name of a computer file, which comes after a (.), and shows what type of file it is
(Definition of extension from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of extension?
Add Cambridge dictionaries to your browser to your website

Definitions of “extension” in other dictionaries

Word of the Day

debut

the occasion when someone performs or presents something to the public for the first time

Word of the Day

Come on – you can do it! Phrasal verbs with ‘come’.

by Liz Walter​,
November 19, 2014
As part of an occasional series on the tricky subject of phrasal verbs, this blog looks at ones formed with the verb ‘come’. If you are reading this blog, I’m sure you already know come from, as it is one of the first things you learn in class: I come from Scotland/Spain.

Read More 

ped-text verb

November 24, 2014
to text someone while walking I’m ped-texting, I’m looking down at my phone, 75 percent of the time.

Read More