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anticatalyst

American  
[an-tee-kat-l-ist, an-tahy-] / ˌæn tiˈkæt l ɪst, ˌæn taɪ- /

noun

Chemistry.
  1. an inhibitor.


anticatalyst British  
/ ˌæntɪˈkætəlɪst /

noun

  1. a substance that destroys or diminishes the activity of a catalyst

  2. another name for inhibitor

"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 anticatalyst

First recorded in 1920–25; anti- + catalyst