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extinctive

American  
[ik-stingk-tiv] / ɪkˈstɪŋk tɪv /

adjective

  1. tending or serving to extinguish.


extinctive British  
/ ɪkˈstɪŋktɪv /

adjective

  1. tending or serving to extinguish or make extinct

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of extinctive

First recorded in 1590–1600; extinct + -ive