When you say "Thank you" to someone these days, which response are you LEAST likely to receive? "No worries." "No problem." "My pleasure." "You're welcome." "Happy to help." "You got it." "Not at all." "Don't mention it." "It was nothing." "Thank YOU!"

If you guessed "You're welcome," you're right.

This gracious phrase, once the universal, reflexive response to expressions of gratitude, has nearly vanished from common parlance.

Picture "you're welcome" as an elegant English aristocrat — let's call him "YW" — who has fallen from favor and fortune and now languishes, degraded and dejected, in the back alleys of London. When American tourists thank him for directions to Trafalgar Square, he's barely able to rasp out a faint, "You're welcome."

How could this happen?

After all, YW inherited an excellent pedigree. The word "welcome" originally meant "desirable guest." So saying "You're [a] welcome" when greeting a visitor to your home meant "You're a valued guest."

Admittedly, YW has always made less sense as a response to "thank you." Upon hearing it, you might ask, "You're welcome ... to what?" Defenders of YW argue that the phrase means "you're welcome to whatever hospitality, gift, service or kindness I can provide." But some find this strained extension of meaning opaque.

The fatal blow for YW might well be its increasing use as a statement of bravado. As New York Times writer Amanda Hess has noted, braggarts and satirists are now deploying YW as a stand-alone, in your-face boast, meaning, "This is what I'm giving you, and you'd better be thankful for it!"

Hess' examples include "You're Welcome America!" (a play featuring Will Ferrell's satiric impersonation of George W. Bush), the Huffington Post's cocky headline "10 Things You Can Stop Doing Now (You're Welcome)," and WWE wrestler Damien Sandow's signature half-nelson slam, the "You're Welcome!" (which certainly gives new meaning to the term "welcome mat").

Hess writes, "'You're welcome' took up its new function as an expression of rudeness at just the moment when the phrase lost its usefulness as a nicety." So YW, an elegant, top-hatted gentleman whose meaning has never been entirely clear, is now being propped up by street thugs as a grotesque manikin of megalomania.

But fear not. Those of us who continue to use YW in its traditional sense, still offer him our simple "thank you" — and await his gracious reply.

Rob Kyff, a teacher and writer in West Hartford, Conn., invites your language sightings. Send your reports of misuse and abuse, as well as examples of good writing, via e-mail to Wordguy@aol.com or by regular mail to Rob Kyff, Creators Syndicate, 737 3rd Street, Hermosa Beach, CA 90254.