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dope fiend

American  
[dohp feend] / ˈdoʊp ˌfind /

noun

Slang: Disparaging and Offensive.
  1. a person addicted to drugs.


Etymology

Origin of dope fiend

First recorded in 1890–95; dope ( def. ) + fiend ( def. ) (in the sense “person addicted to a pernicious habit”)