The phrases are disrespectful, demeaning and, frankly, unimaginative.

But they're annoyingly ubiquitous.

And that was even before The Wall Street Journal provided Sarah Palin a nugget with which to make political hay.

"That's just retarded" and "That's so gay" have become all-purpose put-downs, used in contexts that have nothing to do with cognitively challenged or homosexual individuals.

But just because words and phrases gain currency in the language doesn't make them valuable or essential to discourse.

The problem is, how do you eradicate hurtful expressions from common overuse?

The Journal wasn't actually calling out White House Chief of Staff Rahm Emanuel on his language in a late January story about liberal groups' frustration with the Obama administration.

The story reported that Emanuel, whose foul mouth has been well-chronicled, called it "f—-ing retarded" for the interest groups to run ads attacking conservative Democrats whose votes would be needed on health care legislation.

Palin pounced via Facebook, chastising Emanuel for a "slur on all God's children with cognitive and developmental disabilities — and the people who love them." She didn't take specific issue with his f-bomb, though. Curious, that.

Why did the former Alaska governor's reaction look only partly sincere? Because she then called it acceptable satire for Rush Limbaugh to huff that it's no insult to call "a bunch of people who are retards, retards."

Not that he was defending Emanuel, mind you; Limbaugh used the slur to show his contempt for those liberal groups whose politics he despises.

Seeing its own opportunity, Sen. Kay Bailey Hutchison's campaign followed by telling CNN that Palin buddy Gov. Rick Perry had his own r-word issues.

CNN had Hutchison's campaign manager saying that in a phone call Perry consultant David Carney had called it "just retarded" and "the most retarded thing I've ever heard" for the Republican gubernatorial candidates to wait for their Jan. 14 debate in a building separate from where they'd be speaking.

In these contexts, the r-word seems to mean moronic. But troll the online Urban Dictionary, and the many definitions offered include just the opposite of stupid. Such is slang.

You can also find debates over whether in an earlier r-word version of the Black Eyed Peas hit "Let's Get it Started" the word meant to get crazy dancing or drunk or just slow things down.

Words and their meanings evolve, sometimes in good ways and sometimes in bad.

Words fall into and out of favor.

Sometimes the language changes with the times for perfectly good reasons. (Nothing wrong with "firefighter" instead of "fireman" when the job's no longer gender-restricted.)

Sometimes revisions made in good faith just sound silly or perverse. (Domestic engineer, anyone?)

But whether bigotry, nastiness, vulgarity or meanness become more entrenched or acceptable — and how we prevent that — is more complicated.

It's taken decades and protests and public education and media awareness and shifting generations to purge some of the ugliest of English words from widespread American usage. Yet some persist in private conversation and public confrontations when small minds resort to malicious insults.

At the same time, profanity has coarsened our culture and our everyday lives.

The Federal Communications Commission doesn't much like the f-word in any of its iterations. Nor do I. But think of how many people drop it — or the b-word that rhymes with "witch" — for everything from a threat to a challenge to an epithet, even to an unthinking placeholder like "you know."

Offensive as that is, though, it's not equivalent to an affront toward an entire group of people who have done nothing more than be an easy target for denigration.

How to eradicate offensive speech?

With more speech that asks people to think about what they're saying.

It's ironic that the Palin-Emanuel brouhaha has called attention to the Special Olympics' year-old campaign to raise awareness about "the dehumanizing and hurtful effects" of the r-word.

March 3 is the second "Spread the Word to End the Word" awareness day.

Maybe the organizers could get a plug from President Obama, who on "The Tonight Show" a year ago tactlessly compared his pathetic bowling skills to "like Special Olympics, or something."

It's not political correctness to say that some language is just too rude. That's common courtesy.