blacklist (n.) Look up blacklist at Dictionary.com
also black-list, "list of persons who have incurred suspicion, earned punishment, or are for any reason deemed objectionable by the makers and users of the list," 1610s, from black (adj.), here indicative of disgrace, censure, punishment (a sense attested from 1590s, in black book) + list (n.1). Specifically of employers' list of workers considered troublesome (usually for union activity) is from 1884. As a verb, from 1718. Related: Blacklisted; blacklisting.