irreversible

1 of 2

adjective

ir·​re·​vers·​ible ˌir-i-ˈvər-sə-bəl How to pronounce irreversible (audio)
Synonyms of irreversiblenext
: not reversible
irreversibility
ˌir-i-ˌvər-sə-ˈbi-lə-tē How to pronounce irreversible (audio)
noun
irreversibly
ˌir-i-ˈvər-sə-blē How to pronounce irreversible (audio)
adverb

irreversibility

2 of 2

noun

ir·​reversibility ¦i How to pronounce irreversibility (audio)
¦ir, 
¦iə+
: the quality or state of being irreversible

Synonyms of irreversible

Relevance

Adjective

See All Synonyms & Antonyms in Thesaurus

Examples of irreversible in a Sentence

Adjective He suffered an irreversible loss of vision. The crisis has done irreversible harm to the countries' relations.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
Texas law defines brain death as the irreversible cessation of brain function. — ABC News, 7 Aug. 2026 Beyond the white patches, which disappear when pouch use stops, a lasting concern is gum recession, which is irreversible. — Callie Teitelbaum, CBS News, 5 Aug. 2026 There is something worth protecting in that caution; suffering can distort judgment, and irreversible decisions deserve scrutiny. — Sai Rajagopal, STAT, 4 Aug. 2026 In Verghese’s model, agents can operate within limits, but large, outward, expensive, or irreversible actions still require human approval. — William Jones, USA Today, 3 Aug. 2026 See All Example Sentences for irreversible

Word History

First Known Use

Adjective

1630, in the meaning defined above

Time Traveler
The first known use of irreversible was in 1630

Rhymes for irreversible

See All Rhymes for irreversible

Browse Nearby Words

irreversibility
irreversible
irrevocability
See all Nearby Words

Cite this Entry

“Irreversible.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/irreversible. Accessed 11 Aug. 2026.

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Kids Definition

irreversible

adjective
ir·​re·​vers·​ible ˌir-i-ˈvər-sə-bəl How to pronounce irreversible (audio)
: impossible to reverse
an irreversible chemical reaction
irreversible damage
irreversibility
-ˌvər-sə-ˈbil-ət-ē How to pronounce irreversible (audio)
noun
irreversibly
-ˈvər-sə-blē How to pronounce irreversible (audio)
adverb

Medical Definition

irreversible

adjective
ir·​re·​vers·​ible ˌir-i-ˈvər-sə-bəl How to pronounce irreversible (audio)
: incapable of being reversed : not reversible
an irreversible medical procedure
: as
a
: impossible to make run or take place backward
irreversible chemical syntheses
b
of a colloid : incapable of undergoing transformation from sol to gel or vice versa
c
of a pathological process : of such severity that recovery is impossible
irreversible brain damage
irreversibility
-ˌvər-sə-ˈbil-ət-ē How to pronounce irreversible (audio)
noun
plural irreversibilities
irreversibly
-ˈvər-sə-blē How to pronounce irreversible (audio)
adverb

Legal Definition

irreversible

adjective
ir·​re·​ver·​si·​ble ˌir-rə-ˈvər-sə-bəl How to pronounce irreversible (audio)
: not reversible
an irreversible decision

More from Merriam-Webster on irreversible

Nglish: Translation of irreversible for Spanish Speakers

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