immutable
ih-MYOO-tuh-bul
/ɪˈmjuːtəbl/
Unchangeable over time; unable to be modified, altered, or erased.
Connotes an inherent structural impossibility of change, rather than merely a rule prohibiting change.
The story behind the word. Rooted in the Latin 'immutabilis', combining 'in-' (not) and 'mutare' (to change, source of 'mutation'). It entered Middle English through Old French to describe divine attributes and natural laws that human force could never shift.
Word relationships
- unalterable: Unalterable means cannot be changed by rule or agreement; immutable means inherently incapable of being changed.
- mutable: Mutable means subject to change, alteration, or variation.
Commonly confused with
- permanent: Permanent means intended to last indefinitely, but it can still be destroyed or modified; immutable means structurally impossible to alter.
Word family
- immutability (noun): The quality or state of being unchangeable.
- immutably (adverb): In an unchangeable manner.
Collocations
- immutable record
- immutable law
- immutable data
- immutable truth
Idioms & expressions
- set in stone
- carved in granite
Example sentences
- "Once written to the distributed ledger, the transaction record becomes immutable, preventing retrospective fraud." Cryptographic Integrity
- "Spinoza argued that the laws of nature are absolute and immutable, governing all matter without exception." Philosophical Discourse
- "Functional programming languages rely heavily on immutable data structures to prevent unexpected side effects during parallel execution." Software Engineering
Memory hook
IM-MUTABLE = IMPOSSIBLE to MUTATE (change). Cannot mutate, cannot change.
When not to use
Do not use for temporary habits or reversible decisions; use 'unalterable' or 'permanent' when human resistance to change is involved rather than structural impossibility.
Fun facts
- In modern software development, declaring a variable 'immutable' guarantees that no concurrent thread can secretly modify its memory state.
Related words
Explore more words
irrevocable, mutable, inevitable, perpetual, incorruptible, Inalienable
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