A person who creates or maintains a blacklist; someone who officially excludes others from jobs, opportunities, or services.
From blacklist (list of people considered undesirable) + -er (one who does). Blacklist itself originated in the 17th century as a list of dangerous people, formalized in labor contexts during the 1800s.
During the McCarthy era in 1950s America, movie studio blacklisters held enormous power — they could end careers with a single name added to a list, making the act of listing as powerful as any written contract.
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