Main Entry: ex·tinc·tion

Pronunciation: \ik-ˈstiŋ(k)-shən\

Function: noun

Date: 15th century

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