extinction

noun

ex·​tinc·​tion ik-ˈstiŋ(k)-shən How to pronounce extinction (audio)
plural extinctions
1
a
: the act of making extinct or causing to be extinguished
gradual extinction of the national debt
b
: the condition or fact of being extinct
also : the process of becoming extinct
attempting to save a species from extinction
… at least 17 species of the island's largest mammals, birds, and reptiles were lost in a wave of extinctions that occurred about 1,000 years ago. Pamela S. Cubberly
Now, more than 40 percent of the world's 7,000 or so languages are thought to be at risk of extinction, some with just a handful of elderly native speakers left. Benjamin Plackett
see also mass extinction
2
: the process of eliminating or reducing a conditioned (see conditioned sense 2) response by not reinforcing it
When a rat in a Skinner box presses a lever, a tone sounds momentarily, followed shortly by delivery of food. … After the animal has been conditioned in this way, the experimenter begins extinction, so that when the rat presses the lever neither the tone nor the food appears.Rita L. Atkinson et al.

Examples of extinction in a Sentence

the extinction of all life in the region the extinction of many old traditions Mass extinctions of prehistoric animals are known to have occurred.
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.
At the next annual meeting of the AOU, Allen got three conservation resolutions passed—including one demanding the complete protection of any species on the verge of extinction. Tim Gallagher, Smithsonian Magazine, 20 Nov. 2024 Related article Antarctica’s emperor penguins at risk of extinction due to the climate crisis The animals are only found in the wild in Antarctica, but they are increasingly threatened by the climate crisis. Jack Guy, CNN, 6 Nov. 2024 Tree species face an alarming risk of extinction, and the timing to emphasize this point couldn't be better. Simi Thambi​, Forbes, 29 Oct. 2024 White people are an endangered breed, fighting to delay their extinction. Abrahm Lustgarten, ProPublica, 19 Oct. 2024 See all Example Sentences for extinction 

Word History

First Known Use

15th century, in the meaning defined at sense 1a

Time Traveler
The first known use of extinction was in the 15th century

Dictionary Entries Near extinction

Cite this Entry

“Extinction.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/extinction. Accessed 1 Dec. 2024.

Kids Definition

extinction

noun
ex·​tinc·​tion ik-ˈstiŋ(k)-shən How to pronounce extinction (audio)
1
: an act of extinguishing or an instance of being extinguished
2
a
: the state of being extinct
b
: the process of becoming extinct
3
: the process of eliminating or reducing a conditioned response by not providing the stimulus with which it has become associated by conditioning

Medical Definition

extinction

noun
ex·​tinc·​tion ik-ˈstiŋ(k)-shən How to pronounce extinction (audio)
1
: the process of becoming extinct
the extinction of a species
also : the condition or fact of being extinct
2
: the process of eliminating or reducing a conditioned response by not reinforcing it

More from Merriam-Webster on extinction

Last Updated: - Updated example sentences
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