: one who advocates or practices activism : a person who uses or supports strong actions (such as public protests) in support of or opposition to one side of a controversial issue
- Antiwar activists were protesting in the streets.
- an environmental activist
- The conventional wisdom is that young people no longer care enough to stand up for what is important; that the days of activism and protest have faded into the past, the bailiwick of aging hippies and activists.
- —The Easton (Massachusetts) Journal