When Federated Department Stores in the United States banned employees from saying Merry Christmas to customers last year so they did not discriminate against other religions, a small group boycotted the chain.

Welcome to the frontline of the politically correct war. Supporters say political correctness changes attitudes and removes divisions in society based on race, affluence, physical appearance and social status. They point to the use of words such as "nigger," "cripple" and "lunatic asylum" - now seen as shocking by most people.

Those against political correctness say it suppresses human rights, such as freedom of expression. They claim PC legislation constitutes social engineering by nanny states and attempts by governments to impose their own values.

Over the past year, Laura Midgely, head of the British-based Campaign Against Political Correctness, notes on her website the Home Office decision that the acronym POPO could not be used for its Prolific and Other Priority Offender scheme because it was Turkish for "bottom".

She says officials were told not to use the words "nitty gritty" as it was potentially racist because it could refer to the grit found at the bottom of slave ships.

In New Zealand, right-winger David Farrar, writer of kiwiblog, adds a few local examples such as former Labour MP Lesley Soper calling for maiden speeches to be renamed, a call for bullet points to be called dot points as bullets have a militaristic connotation, and banning (in Ireland) the word "brainstorming" because it might offend people with epilepsy as well those with brain tumours or brain injuries.

At a more serious level, he views as excessively PC Helen Clark's refusal to allow grace to be said for the Queen but agreeing to enter a mosque through the women-only back door.

Auckland University law professor Paul Rishworth says political correctness can take credit for making a positive change to society.

"Without a fairly robust awareness of the existence of minority groups, then the sort of society we would have would be one that just suits the majority.

"We always have to be alert that we could just deny the existence of minority views, and political correctness has made us more aware of that."

The online encyclopaedia Wikipedia notes PC language such as Star Trek's opening phrase "To boldly go where no man has gone before", which became "to boldly go where no one has gone before".

It notes the demise of terms such as cripple, retarded, mongolism (Down syndrome) and spastic (cerebral palsy) to those such as "special needs" and "physically challenged".

Mr Rishworth said a lot of what was labelled political correctness was plain old good manners so others were not offended.

"Those who say language changes attitudes are making a fair point. But it goes too far, for instance, when a genuine disagreement by someone about something is classified as 'discrimination' or 'hatred'.

"You often get that in areas of sexual orientation, for example. Of those who think homosexuality is wrong, it's too easy to say they hate, when really they are only describing the phenomenon of disagreement."

He said some attempts were excessive, "but that doesn't mean the basic idea is not a good one".

Banned in the name of political correctness

Racist

* Golliwogs, the black-faced dolls, which first appeared in the late 19th century and became villains in Noddy stories, went out of favour as they were considered to convey racist overtones.

* Little Black Sambo and Rupert Bear books such as Rupert on Coon Island were ostracised because they harked back to a legacy of slavery.

Sexist

* Barbie changed shape in 1998, losing the large breasts and tiny waist.

Violent

* Punch and Judy puppet shows came under attack after two centuries because councils deemed a man who beat his wife with a stick to be a bad role model.

Offensive

* British banks are banning piggybanks as they may offend Muslims, who do not eat pork for religious reasons.

* Banned: the words spinster and bachelor will be banned on British marriage certificates as the Registrar General says they cannot be applied to homosexuals. "Single" will be used instead.