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immutable

/ɪˈmjuː.tə.bəl/
IELTSAcademic
adjective

Describes something that cannot be changed, altered, or modified in any way. It stays exactly the same forever, no matter what happens.

  • The laws of mathematics are immutable and apply everywhere in the universe.
  • Some moral principles are considered immutable across all human cultures.
  • The scientist treated the speed of light as an immutable constant.

Adinary Nuance

"Immutable" is often used where "permanent," "fixed," or "unchangeable" might also fit, but each word has a different strength. "Permanent" means something lasts a very long time or indefinitely — but it could still change; a permanent job can end. "Immutable" is much stronger: it means change is simply not possible, ever. "Fixed" suggests something has been set in place by a decision, while "immutable" suggests a deeper, natural impossibility of change. Choose "immutable" in academic or IELTS writing when you want to argue that something is beyond any human or natural force to alter.

In other languages

Vietnamese
Bất biến
Spanish
Inmutable
Chinese
不变的
Japanese
不変の
Korean
불변의

Etymology

From Latin "immutabilis," combining "in-" (not) and "mutabilis" (changeable), from "mutare" meaning "to change." The word entered English in the late 14th century, mainly through scholarly and religious writing.

Common phrases

immutable lawsimmutable truthimmutable principlesimmutable record

Synonyms

Related words

Frequently asked questions

Is 'immutable' formal or informal?
It is formal and academic. It fits IELTS essays, legal documents, and philosophical writing well. In everyday speech, most people prefer 'unchangeable' or 'fixed.'
What is the difference between 'immutable' and 'permanent'?
'Permanent' means something lasts a very long time or indefinitely, but it could still change in theory. 'Immutable' is stronger — it means change is completely impossible, not just unlikely.
Can I use 'immutable' in an IELTS essay?
Yes, it is excellent IELTS vocabulary. It works well in argumentative or discursive essays about laws, scientific facts, or fundamental values. Just make sure the context truly implies something that cannot be changed at all.
Is 'immutable' common in everyday English?
Not in casual conversation. You will mostly encounter it in academic texts, philosophy, law, and computer science. In daily speech, people usually say 'it can't be changed' or 'it's set in stone.'