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.
The study does not establish that every future change is irreversible or that Thwaites must accelerate toward total collapse. — Kaif Shaikh, Interesting Engineering, 17 Oct. 2026 Holtec International bought it and began dismantling it, though none of the steps were irreversible. — Jennifer McDermott, Los Angeles Times, 16 Oct. 2026 These accelerating and intensifying changes could raise the risk of reinforcing feedback loops and crossing tipping points—critical thresholds that, when crossed, can lead to accelerating and often irreversible environmental changes. — Simmone Shah, Time, 14 Oct. 2026 Where agents may take irreversible financial or legal actions, the figure is 29% against 13%. — Nick Lichtenberg, Fortune, 13 Oct. 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 22 Oct. 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
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