By the 1980s, feminism had ceased being her primary focus, and she spent her last decades focused on issues of aging, families, work and public policy. She wrote six books and held teaching posts at many institutions, including UCLA and USC.
Friedan did not conform to conventional notions of feminine beauty or decorum. She was short -- 5 feet 2 -- and stocky, with a hawklike nose, large, deep-set eyes and a gravelly voice that no one could call timid. She was fast-talking, impatient and abrasive. Her rudeness was especially perplexing when she directed it at other women. "I could be," she acknowledged in later years, "a bad-tempered bitch."
She remained formidable in her old age. Even as she was approaching 80 and enjoying her role as doting grandmother of nine, she could demolish interviewers who asked what she considered inane questions.
Yet she always bore a trace of the little girl from Peoria, Ill., at times giddy, vulnerable and stuck on appearances. Peoria, she once observed, was the source of all her hang-ups.
Friedan was born Bettye Goldstein on Feb. 4, 1921, the year after American women won the right to vote. She was the oldest of three children of jewelry store owner Harry Goldstein, a Russian Jew, and the former Miriam Horwitz.
Although a sickly child who suffered from asthma and vision problems, Bettye (who later dropped the e from the end of her first name) was precocious and skipped a year of school. In high school she was valedictorian, but her braininess, she said, made her feel "like a freak."
Anti-Semitism barred her father, a successful businessman, from joining the country club and other elite Peoria circles, and it kept Bettye and her sister out of high school sororities. "When you're a Jewish girl who grows up on the right side of the tracks in the Midwest, you're marginal. You're in, but you're not," she said, "and you grow up an observer."
Her mother was an unhappy housewife whose disposition and health dramatically improved when her husband's health faltered and she took over management of the jewelry business. In her 1976 book "It Changed My Life," Friedan said her mother's discontent gave her an early glimpse of the perils of the malaise she would later call the "feminine mystique."
Envious of her mother's social grace and her sister's beauty, Friedan did not feel at home until she arrived at Smith College in the late 1930s.