She is known as a campaigner for women's rights.
Environmental activists held a demonstration.
athlete; sporty person
Describes someone who is physically active or excels at sports. Less common than 運動選手 for professional athletes; often implies a general love for physical activity.
He has been a sporty person since childhood and runs every day.
Compound of 運動 (movement, exercise) and 家 (person, specialist). The activist sense likely developed from the idea of a person engaged in a social movement, while the athlete sense comes from physical exercise.