She was an active participant in the women's movement of the 1960s.

women's 是 woman 的所有格形式，表示"女性的、妇女的"。 movement 是名词，意思是"运动"，指有组织的社会或政治活动。 women's movement 指"妇女运动"，是为争取女性平等权利而开展的社会运动。