actionist

noun

1. (capitalized, sometimes)One taking part in the actionism movement.

   “The most radical of all 1960s performers, the Viennese Actionists explored a broad spectrum of transgressions up until the end of the 1960s: sodomy, rape, necrophilia, zoophilia, anthropophagy, self-mutilation, and animal sacrifices.”

2. A shareholder in a joint-stock company.
3. Synonym of activist.

   “Generally speaking, the risks to the actionists on the one hand, and to the system against which they take action on the other, are least in the case of nonviolent protest and greatest in the case of nonviolent intervention.”