irreversible

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

Synonyms of irreversible

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Examples of irreversible in a Sentence

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.
Instead, he was left to navigate years of uncertainty and irreversible damage. — Borna Nyaoke-Anoke, STAT, 30 July 2026 Policy guardrails must now be put in place, prior to any additional approvals, to prevent irreversible damage to the global climate as well as local air and water quality, freshwater supplies, and household finances. — John Kostyack, Forbes.com, 29 July 2026 Years ago, a brutal match left his childhood best friend Krit with irreversible brain damage. — Melanie Goodfellow, Deadline, 29 July 2026 So slow down whenever a decision is large, irreversible, tax-related or being sold to you. — Pawan Jain, The Conversation, 29 July 2026 See All Example Sentences for irreversible

Word History

First Known Use

1630, in the meaning defined above

Time Traveler
The first known use of irreversible was in 1630

Rhymes for irreversible

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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 3 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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