One impediment to our widespread acceptance of Ms. is the cloud of misunderstanding that still surrounds it. A 1998 study by Barbara Kelly of "folklinguistic attitudes" to the use of the term Ms. showed that many people link it to marital status. They assume it refers to a divorced, widowed or unmarried woman; that it deliberately conceals marital status, highlights single status or shows that a woman is not committed to her husband.

How ironic that a title created to neutralize the issue of wedlock came to be so elaborately misconstrued in that very context. And let's not chalk this up to men: Fully 49 percent of the women interviewed by Kelly didn't understand how Ms. should be used.

Stranger yet is the fact that many interpretations of female courtesy titles directly contradict each other, indicating that each has its own social Rorschach effect. One woman told me that Ms. makes her think of "a stuffy socialite who lunches at Le Cirque." Another said, "I do know some women who 'tolerate' being called Mrs. (with the husband's first and last name) in social circles. This is common among the wealthy, where for some reason they can't break tradition and give women individual identities."

One woman who uses Ms. surmised that some people use Mrs. because they don't want their husbands to think they're "passing themselves off as not married." (Would we ever suspect a Mr. of doing this?) Some women change their titles by the hour or the year (Ms. until 5 p.m., Mrs. after hours; Miss to people who knew them before they were married ...), suggesting multiple personalities fragmented along the lines of work and marriage.

The contradiction I see has nothing to do with taking a man's name, nor does it apply to befuddled youths who misuse Ms. simply because courtesy titles in general are in decline. It's the conditional use of Ms. that jars, implying that sexual/marital neutrality is suitable in the workplace but not in the outside world.

Working women who shift to Mrs. once they are away from their desks assuage a distinctly Victorian fear: that professional achievement will magically unsex them. As Carl Jung put it: "In taking up a masculine calling, studying and working in a man's way, woman is doing something not wholly in agreement with, if not directly injurious to, her feminine nature."

So the Ms. who socked it to the district attorney at work and goes home to become Mrs. proves that she hasn't sacrificed her marriageability on the altar of her career. Her feminine currency is validated with every utterance of the title, because at its crudest, Mrs. trumpets sexual status: taken.

In the context of women's history, the fortification of this home/work divide is a dangerous business: It contradicts the logic underpinning some of the most important family-friendly initiatives on the public table: flextime, parental leave, job sharing and on-site day care -- all designed to allow personal and professional identities to overlap by strengthening connections between them.

This division reinforces the Midwestern stereotype that an independent woman (Ms.) and a good wife (Mrs.) can't be the same person, and it's the reason Hillary Rodham, lawyer, was reborn as Hillary Rodham Clinton, wife, when her career became a potential liability for her husband's. At its most extreme, this work/home, public/private dualism drives every repressive patriarchy in the land, from the Mormon Church to the Taliban.

On its evolutionary journey from feminist red flag to Everywoman courtesy title, Ms. still roils with semiotic undercurrents churned up during feminism's second wave. But that's no excuse for using it selectively. Tell me you reject Ms. because you're not a feminist, or that the title is tethered to a movement that overlooked you, or that your mother shoved it down your throat. Tell me that your marriage is your greatest accomplishment, or that you were married in 1956. But don't say Ms. describes you at work and not at home. It's just so 20th century.

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