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Synonyms

immutable

American  
[ih-myoo-tuh-buhl] / ɪˈmyu tə bəl /

adjective

  1. not mutable; unchangeable; changeless.

  2. Computers. (in object-oriented programming) of or noting an object with a fixed structure and properties whose values cannot be changed.


immutable British  
/ ɪˈmjuːtəbəl /

adjective

  1. unchanging through time; unalterable; ageless

    immutable laws

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • immutability noun
  • immutableness noun
  • immutably adverb

Etymology

Origin of immutable

First recorded in 1375–1425; late Middle English, from Latin immūtābilis; im- 2, mutable

Explanation

If you can't change it, it's immutable. There are many things in life that are immutable; these unchangeable things include death, taxes, and the laws of physics. The adjective immutable has Latin roots that mean "not changeable." The Latin prefix for not is in, but the spelling changes when the prefix is put before the consonant m. It is im before a root word starting with m as in immutable. If you learn this rule, you'll know the immutable fact that immutable begins with i-m-m.

Keep Reading on Vocabulary.com

Vocabulary lists containing immutable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But that’s not the most important part, which is that this is a beautiful, solid, immutable printed book.

From Los Angeles Times • Dec. 8, 2025

But so far, those limitations have involved just a small percentage of prop bets for one simple and immutable reason.

From The Wall Street Journal • Nov. 16, 2025

If there’s one immutable fact about TV, it is that there’s no such thing as a sure thing.

From Salon • Nov. 16, 2025

AI appears to be running up against some immutable laws of common sense.

From Barron's • Oct. 10, 2025

Facts are made in the image not of people, who misremember, misquote and misrepresent, but of books, immutable but mobile.

From "The Invention of Science" by David Wootton