Definition of extinction
1
: the act of making extinct or causing to be extinguished
2
: the condition or fact of being extinct or extinguished
also
: the process of becoming extinct
extinction of a species
3
: the process of eliminating or reducing a conditioned response by not reinforcing it
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Merriam-Webster unabridged
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Time Traveler for extinction
The first known use of extinction was in the 15th century
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