irreversible

adjective

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

Synonyms of irreversible

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.
For some galaxies, the shutdown might be irreversible, a truly permanent end to star formation, likely due to severe gas loss. Paul Sutter, Space.com, 25 Apr. 2026 Yet there is nothing eternal or canonical or irreversible about this system. Jessica Winter, New Yorker, 23 Apr. 2026 This control sequence, called a Hamiltonian, acts like Maxwell’s demon, flip-flopping a supposedly irreversible sequence of events forward to backward. Stephanie Pappas, Scientific American, 21 Apr. 2026 Painting can be a dramatic transformation, but the changes are often irreversible without incurring high costs or degrading property. Abby Wolner, Better Homes & Gardens, 21 Apr. 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

Browse Nearby Words

Cite this Entry

“Irreversible.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/irreversible. Accessed 28 Apr. 2026.

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 noun
irreversibly 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 noun
plural irreversibilities
irreversibly 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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