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English definition of “extension”

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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).
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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

extension

adjective [only before noun] uk   /ɪkˈsten.ʃən/ us  
intended to support students' learning by making them try different or more difficult things in addition to their basic work: The book includes lesson plans and extension activities. US ( UK extramural) organized by a college or university, etc. for students who are not able to be physically present in class: extension classes/courses
(Definition of extension from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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