English Reference
noun

extinction

n.
US /ɪkˈstɪŋkʃən/ UK /ɛkstˈɪŋkʃən/ ex·tinc·tion UK spelling extinctions

  1. 01 B2 Upper Intermediate

    the situation where a type of animal or plant stops existing completely.

    the permanent disappearance of a species or higher taxonomic group from the earth.

    Simple

    The sudden extinction of the dinosaurs happened millions of years ago.

    In context

    Conservationists are working tirelessly to prevent the total extinction of the northern white rhino, whose population has dwindled to just a few individuals.

  2. 02 C1 Advanced Technical Psychology

    the process where a learned behavior or habit slowly disappears because it is no longer rewarded.

    the gradual weakening and eventual disappearance of a conditioned response when the stimulus is no longer reinforced.

    Simple

    If you stop giving the dog treats for sitting, the behavior may face extinction.

    In context

    The therapist explained that the extinction of the patient's phobic response would require repeated exposure to the trigger without any negative consequences.

  3. 03 C2 Proficiency Technical Science

    the way dust and gas in space block or scatter light from stars.

    the reduction in the intensity of light or other radiation as it passes through a medium, particularly interstellar dust.

    Simple

    Astronomers must account for extinction when measuring how bright a distant star really is.

    In context

    Interstellar extinction can significantly redden the appearance of distant galaxies, as shorter wavelengths of light are scattered more easily by cosmic dust.

University of Washington researchers are working with the Samish Indian Nation to bring this 24-armed creature back from the brink of extinction.

NPR· 16 Aug 2026

Researchers aren't releasing butterflies to prevent extinction anymore—they're releasing them to expand a recovering population.

Phys.org· 14 Aug 2026

From late Middle English, borrowed from Latin extinctio (“extinction, annihilation”), from extinguere, past participle extinctus (“to extinguish”); see extinguish.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin extinctio
Level B2 · Upper Intermediate
Frequency Frequent
Updated