extension

15 synonyms and 1 antonym for extension, grouped by meaning and by how common each one is.

Noun — An extra part added to something to make it larger or longer, or an extra period of time granted beyond an original deadline.

Synonyms

Everyday swaps

Common words most readers know — safe in any writing.

addition wing reference

Less common

Still standard English, but they carry more weight.

enlargement propagation annex module

Rare, literary or technical

Precise, but they will stand out — check the sense before using one.

elongation annexe prolongation postponement lengthiness denotation add-on plug-in

Synonyms by Meaning

1. noun

An extra part added to something to make it larger or longer, or an extra period of time granted beyond an original deadline.

“They built a single-storey extension at the back of the house.”

elongation addition annexe enlargement prolongation postponement propagation annex wing lengthiness reference denotation

Opposites

flexion

2. noun

A small program that adds features to a web browser or other software.

“Install the extension and a save button appears in the toolbar.”

add-on plug-in module

How to use extension

The word patterns that sound natural to a native speaker.

build an extension request an extension browser extension extension number hair extensions

Etymology

From Latin extensio, from extendere ('to stretch out'), from ex ('out') plus tendere ('to stretch').

Full origin of extension →

Frequently asked questions

What is the difference between an extension and a plug-in?

In browsers the terms now overlap heavily. Historically a plug-in was separate software that let the browser handle a media type it could not read on its own, while an extension is written for the browser itself to add features to the interface. Modern browsers have retired plug-ins and use 'extension' for almost everything.

What is a file extension?

It is the suffix after the final dot in a filename, such as .pdf or .jpg, which tells the operating system what kind of file it is and which program should open it. Changing it does not convert the file; it only changes what the system expects.

How do you ask for a deadline extension?

Ask early, before the deadline passes, state plainly why you need it, and propose a specific new date rather than an open-ended delay. Confirming it in writing protects both sides.

People also searched

addition reference wing module annex enlargement propagation annexe denotation postponement prolongation lengthiness

Nearby words

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