Helen Gurley Brown, the longtime editor of Cosmopolitan magazine who invited millions of women to join the sexual revolution, has died at age 90.

Brown died Monday at a hospital in New York after a brief hospitalization, Hearst media company CEO Frank A. Bennack, Jr. said in a statement.

“Sex and the Single Girl,” her grab-bag book of advice, opinion, and anecdote on why being single shouldn’t mean being sexless, made a celebrity of the 40-year-old advertising copywriter in 1962.

Three years later, she was hired by Hearst Magazines to turn around the languishing Cosmopolitan and it became her bully pulpit for the next 32 years.

She said at the outset that her aim was to tell a reader “how to get everything out of life — the money, recognition, success, men, prestige, authority, dignity — whatever she is looking at through the glass her nose is pressed against.”

“It was a terrific magazine,” she said, looking back when she surrendered the editorship of the U.S. edition in 1997. “I would want my legacy to be, ‘She created something that helped people.’ My reader, I always felt, was someone who needed to come into her own.”

Along the way she added to the language such terms as “Cosmo girl” — hip, sexy, vivacious and smart — and “mouseburger,” which she coined first in describing herself as a plain and ordinary woman who must work relentlessly to make herself desirable and successful.

She put big-haired, deep-cleavaged beauties photographed by Francesco Scavullo on the magazine’s cover, behind teaser titles like “Nothing Fails Like Sex-cess — Facts About Our Real Lovemaking Needs.”

Male centerfolds arrived during the 1970s — actor Burt Reynolds’ (modestly) nude pose in 1972 created a sensation — but departed by the ’90s.

Brown and Cosmo were anathema to militant feminists, who staged a sit-in at her office. One of them, Kate Millet, said, “The magazine’s reactionary politics were too much to take, especially the man-hunting part. The entire message seemed to be ‘Seduce your boss, then marry him.’”

Another early critic was Betty Friedan, who dismissed the magazine as “immature teenage-level sexual fantasy” but later came around and said Brown, “in her editorship, has been a rather spirited and gutsy example in the revolution of women.”

“Bad Girls Go Everywhere,” the 2009 biography of Brown by Jennifer Scanlon, a women’s studies professor, argued that her message of empowerment made Brown a feminist even if the movement didn’t recognize her as such.

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