extinct

American  

[ik-stingkt] / ɪkˈstɪŋkt /

adjective

1. no longer in existence; having ended or died out.

   extinct pre-Colombian societies.

2. Biology, Ecology. (of a plant or animal species) having no living member remaining anywhere, not in the wild, in a naturalized population, nor in captivity, as categorized by the IUCN Red List: EX

   a list of extinct animals that once inhabited the Isle of Man.

   Synonyms:

   gone, defunct

3. no longer in use; obsolete.

   an extinct custom.

   Synonyms:

   archaic

4. extinguished; quenched; not burning.

   evidence of a half dozen extinct campfires.

   Synonyms:

   out

5. Geology. (of a volcano) not having erupted for at least 10,000 years and not expected to erupt again.

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extinct British  

/ ɪkˈstɪŋkt /

adjective

1. (of an animal or plant species) having no living representative; having died out

2. quenched or extinguished

3. (of a volcano) no longer liable to erupt; inactive

4. void or obsolete

   an extinct political office

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extinct Scientific  

/ ĭk-stĭngkt′ /

1. Having no living members. Species become extinct for many reasons, including climate change, disease, destruction of habitat, local or worldwide natural disasters, and development into new species (speciation). The great majority of species that have ever lived—probably more than 99 percent—are now extinct.

2. No longer active or burning, as an extinct volcano.

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Related Words

See dead.

Other Word Forms

• nonextinct adjective
• unextinct adjective

Etymology

Origin of extinct

First recorded in 1400–50; late Middle English, from Latin ex(s)tinctus, past participle of ex(s)tinguere; extinguish ( def. )

Example Sentences

And if doubles are an endangered species, triples are practically extinct.

From The Wall Street Journal • Mar. 24, 2026

"Without any intervention, the 17 species on this Category X list will be extinct within a generation," Professor Fensham said.

From Science Daily • Mar. 13, 2026

"But the discovery of two species, thought to have been extinct for thousands of years, is remarkable."

From BBC • Mar. 6, 2026

West Papua reveals two species that we thought were extinct.

From MarketWatch • Mar. 6, 2026

All the birds go extinct in a fell swoop.

From "The Gene" by Siddhartha Mukherjee