One who is politically active in the role of a citizen; especially, one who campaigns for change.
It has jailed environmental activists and is planning to limit the power of judicial oversight by handing a state-approved body a monopoly over bringing environmental lawsuits.2013 August 10, “Can China clean up fast enough?”, in The Economist, volume 408, number 8848:
The six activists will now face a retrial at Highbury Magistrates' Court, in front of a new judge.2023 January 11, “Network News: Court decision overturned: Six HS2 activists face retrial”, in RAIL, number 974, page 9:
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One who is conspicuously active in carrying out any occupational or professional functions.
Even in the area of free speech, Justice Harlan sometimes emerged as more activist than his brother1971 September 26, “They Will Affect The Nation For Years To Come”, in New York Times:
These cell-phoned crowds are activist but not militant; today’s “mobe” is no mob.2000 April 13, William Safire, “Essay: Here Come the Big Parades”, in The New York Times, New York, N.Y.: The New York Times Company, →ISSN, →OCLC, archived from the original on 27 May 2015:
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Now GM has what may well be the most activist board ever.2009 December 10, “Angst Over GM's Activist Board”, in BusinessWeek:
Gov. Chris Christie has long complained that New Jersey's Supreme Court is too liberal and too activist2012 June 1, “Gov. Christie's court pick blocked”, in Cherry Hill Courier Post (NJ):