extension
HighNeutral/Formal, used across all registers from technical to everyday.
Definition
Meaning
The act of making something longer or larger; a part that is added to something to enlarge or prolong it.
The action of extending or being extended in various contexts: additional time granted; a subsidiary telephone line; an extra period of study; a continuation or development.
Linguistics
Semantic Notes
The word covers a wide semantic field from physical lengthening to abstract concepts of scope, time, and influence. It often implies something is an addition to or continuation of a main entity.
Dialectal Variation
British vs American Usage
Differences
In UK academic contexts, 'extension' for an essay deadline is common. In US real estate/business, 'file extension' (e.g., .doc) is a high-frequency collocation. The phrase 'extension cord' is more common in US English; 'extension lead' is more common in UK English.
Connotations
Largely identical. Can carry a neutral (technical) or slightly negative (bureaucratic delay) connotation depending on context (e.g., 'requesting an extension').
Frequency
Very high frequency in both varieties, with slight domain-specific variations (e.g., more frequent in US tech contexts).
Vocabulary
Collocations
Grammar
Valency Patterns
extension of [NOUN]extension to [NOUN]extension for [PURPOSE/REASON]extension on [DEADLINE/CONTRACT]Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “by extension (logically following from)”
- “on extension (of a telephone line)”
- “no extension of time will be granted (formal)”
Usage
Context Usage
Business
Contract extension, project extension, filing for a tax return extension.
Academic
Essay deadline extension, extension course (continuing education), logical extension of a theory.
Everyday
Kitchen extension, phone extension, asking for more time.
Technical
File name extension (.pdf), browser extension, hyperextension of a joint.
Examples
By Part of Speech
verb
British English
- The council may extend the consultation period.
- We need to extend the lease on the flat.
American English
- The university will extend the application deadline.
- They plan to extend the highway another fifty miles.
adverb
British English
- The road continues extensively into the moor.
- The theory was extendedly debated.
American English
- The network was extendedly out of service.
- She argued extensively for the policy change.
adjective
British English
- The extendable ladder wasn't long enough.
- She took an extension course in psychology.
American English
- The extendable dining table seats twelve.
- He completed an extension program online.
Examples
By CEFR Level
- My phone has a long extension cord.
- We built an extension on our house.
- The file has a .docx extension.
- I need an extension for my homework.
- She added hair extensions for the party.
- By extension, his theory applies to economics too.
- The architect designed a modern glass extension to the Victorian property.
- Negotiations centred on a six-month extension of the ceasefire.
- The logical extension of his argument leads to a contradiction.
- The court granted a discretionary extension of the filing deadline owing to extenuating circumstances.
- The franchise's global extension was predicated on rigorous cultural adaptation.
- This philosophical concept finds its extension in the realm of applied ethics.
Learning
Memory Aids
Mnemonic
Think of EX-TEN-SION: it makes something EXpand to be TEN times bigger, or stretch out in one SION (direction).
Conceptual Metaphor
IDEAS/INFLUENCE ARE PHYSICAL ENTITIES THAT CAN BE STRETCHED (e.g., 'the extension of democracy'). TIME IS A PHYSICAL LENGTH (e.g., 'an extension of the deadline').
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid using 'расширение' (broadening/widening) for all contexts; use 'продление' for time extensions.
- Do not translate 'file extension' literally as 'расширение файла'; it is 'расширение имени файла' or 'тип файла'.
- Building 'extension' is often 'пристройка', not just 'расширение'.
Common Mistakes
- Confusing 'extension' with 'extent' (the degree or scope of something).
- Misspelling as 'extention'.
- Using wrong preposition: 'extension of a deadline', not 'extension for a deadline' (though 'extension for submitting' is correct).
Practice
Quiz
In which context is the word 'extension' LEAST appropriate?
FAQ
Frequently Asked Questions
No, it is widely used for abstract concepts like time, influence, meaning, and digital components (e.g., browser extension, deadline extension).
'Extension' often implies lengthening in one dimension or continuing something existing. 'Expansion' implies growth in multiple dimensions, volume, or scale (e.g., business expansion, expansion of gases).
Common phrases are: 'I would like to request an extension on the deadline for [assignment] due to [reason].' or 'Would it be possible to grant me a short extension?'
It is the suffix at the end of a filename (e.g., .txt, .jpg) that indicates the file format and what type of data it contains, telling the operating system which program should open it.
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