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-nik

American  
  1. a suffix of nouns that refer, usually derogatorily, to persons who support or are concerned or associated with a particular political cause or group, cultural attitude, or the like.

    beatnik, filmnik; no-goodnik; peacenik.


-nik British  

suffix

  1. denoting a person associated with a specified state, belief, or quality

    beatnik

    refusenik

"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 -nik

< Yiddish ( nudnik ) < Slavic: a personal suffix in Slavic languages in contact with Yiddish