Acceptance of the word, however, also reignites an old argument, one most forcefully made by Eve Ensler in “The Vagina Monologues.” Over a decade ago, Ms. Ensler wrote that “what we don’t say becomes a secret, and secrets often create shame and fear and myths.” Vagina, her widely performed series of monologues declared, is too often an “invisible word,” one “that stirs up anxiety, awkwardness, contempt and disgust.”

Dr. Carol A. Livoti, a Manhattan obstetrician and gynecologist and an author of “Vaginas: An Owner’s Manual” (Thunder’s Mouth Press, 2004), said vajayjay and other euphemisms and slang offend her and can render women incapable of explaining their symptoms to health professionals. “I think it’s terrible,” Dr. Livoti said. “It’s time to start calling anatomical organs by their anatomical name. We should be proud of our bodies.”

“It seems like a step backward,” she added.

In a voice-mail message left for a reporter, Gloria Steinem said she hopes the women using vajayjay are doing so because they think it is more descriptive than vagina, not because they are squeamish.

Technically speaking, the vagina is the canal that leads from the uterus to the outside of the body, a fact that has led both Ms. Ensler and Ms. Steinem to write that vagina — while not a word that should be stigmatized — is inadequate because it is not inclusive enough. It does not, they have pointed out, include the labia and clitoris, the nerve-rich locus of a woman’s sexual pleasure. “I’m hoping that the use of this new word is part of the objection to only saying vagina since it doesn’t include all of women’s genitalia, for instance the clitoris, in the way that vulva does,” Ms. Steinem said.

Another view was offered by John H. McWhorter, a linguist and a senior fellow at the Manhattan Institute, who pointed out that the women associated with introducing the word — Ms. Winfrey, the Miranda Bailey character on “Grey’s Anatomy” — are middle-age African-Americans.