“Even though the people against us are very, very sure,” she said, “we don’t have to be that sure. Feminism is inevitably uncertain and unresolvable.”

Ann Barr Snitow was born on May 8, 1943, in Manhattan to Charles and Virginia (Levitt) Snitow. Her father was a lawyer and also produced trade shows. Her mother was a high school English teacher and later became active in Jewish causes; she served as president of the women’s division of the American Jewish Congress and supported projects in Israel, such as a shelter for battered women and the first lesbian magazine.

When Ann was a toddler, the family moved to Scarsdale, N.Y. She graduated from Cornell in 1965 with a bachelor’s degree in English and began work on her doctorate in English at the University of London. But by 1968, she was eager to join in the political upheaval in the United States and so broke off her studies and went back to New York. (She would not earn her Ph.D. until 1979.)

“To sit in the British Library while the world was exploding was not the right thing,” she said in a 2016 interview with The Nation.

In 1977, while she was working at the radio station, a listener named Daniel Goode, who was captivated by her, wrote her a letter. She never answered, so he called in to the show. They met for lunch, and the next year moved in together. They were married 26 years later, in 2004. Mr. Goode, a composer and clarinetist, said they finally got married to ensure full property rights for the remaining spouse when the other was gone.

Mr. Goode survives Ms. Snitow, as does her brother and her niece, Tania Chelnov-Snitow .

When she left London, Ms. Snitow emerged on the feminist scene in New York in 1969 as a founding member of the New York Radical Feminists, a consciousness-raising group — one of many in the era’s much-splintered world of feminist organizations. The goal of this group was to create a more broad-based, non-hierarchical women’s movement, as outlined by the writer Vivian Gornick in her seminal call to arms, “The Next Great Moment in History is Theirs,” published in 1969 in The Village Voice.

Its leaders left within a year because of internal disputes, and the organizational structure was dismantled. Ms. Snitow joined another consciousness-raising group that met regularly for the next 15 years.