a person who uses or supports strong actions (such as public protests) in support of or opposition to one side of a controversial issue. An activist is someone who is active in campaigning for change, normally on political or social issues. Activism is what activists do, that is, the methods they use in order to bring about change. Forms of activism range from mandate building in a community (including writing letters to newspapers), petitioning elected officials, running or contributing to a political campaign, preferential patronage (or boycott) of businesses, and demonstrative forms of activism like rallies, street marches, strikes, sit-ins, ...