The word yuon is sprinkled liberally throughout Cambodian daily life. In a restaurant one can order somlau meju yuon, Vietnamese sour soup, or one can insult the waiter with the term.

But as political pressure mounts ahead of the July 27 election, the word is ringing out at political rallies. Campaign speeches about the threat of yuon-usually over the familiar refrain of Vietnamese border incursions-are regular occurrences at Funcinpec and Sam Rainsy Party (SRP) gatherings.

It remains an unmentionable topic for some, but controversy over its use has grown. An increasing number of people are galvanized by what they see as its racist and pejorative overtones.

However, Bora Touch, a Khmer-Australian lawyer who regularly sounds off on the issue, maintains that perception is misinformed. He rejects dropping the word for the sake of "political correctness".

"The term 'Yuon' has become so controversial that the Khmers and the Khmer language have become the victims," he wrote in a response to Washington Times article last year. "It has become a piece of Khmer tradition and language."

By all accounts, a historical basis for the word does exist, although not only in Khmer heritage. The 2003 Historical Dictionary of Cambodia traces the word to the Sanskrit root yavana, meaning 'barbarians'. The entry adds that: "[Yuon] is used in political speech ... to indicate national superiority and ethnic hostility."

It is clear the term, apart from the oft-cited 1968 Buddhist Institute Dictionary entry as "ethnic people from Tonkin, Annam, and Cochinchina", has more than one meaning.

Today many Cambodians say the term was used colloquially in the 1960s to refer to Vietnamese without negative connotations. Some claim a 'Black Paper' issued by the Khmer Rouge in 1979 was the first official mention of a more sinister version of the term to mean 'savage'. However, earlier dictionaries also define the word as 'barbarian' and 'red ant'.

Whatever its origins, yuon remains a part of the deep-rooted resentment many Khmers feel toward the Vietnamese reflected in gruesome myths or sayings passed down over generations. A common Khmer saying is: 'Khmae men jaol kabuen; Yuon men jaol put', which means: Cambodians never abandon rules; the Vietnamese never abandon deception.

In that context, it is not surprising that people find the word inspires anger, resentment and violence. The term came up as the motive for at least one murder in recent years, when a Khmer man was killed after referring to four ethnic Vietnamese as yuon.

Tong Vey, 47, a Cambodian citizen of Vietnamese heritage, says hearing the word makes him angry.

"When someone says this word, I feel they are cursing me," says Tong. "I feel so angry, but I don't answer them because I think that the speaker simply doesn't know that Vietnamese people living here are kind."

Use of the term grates on others too. Somsri Sananuntafuk, an election coordinator from Thailand who works with the Asian election monitoring organization ANFREL, says it should not be used as it is so disliked. She notes the word does not carry the same connotations in Thailand.

"But over here [in Cambodia], I think we should not use [it]. It can be a human rights issue if you consider it in terms of racism."

And she feels parties should not use the term as it promotes racial divisions: "They don't take this to be a problem? This is."

A sharp divide exists among political parties about its use. PM Hun Sen has attacked the SRP leader Sam Rainsy for his use of the word, which the PM described as highly derogatory and racist.

Political opponents dismiss that as an attempt to distract attention from Hun Sen's deep ties to Vietnam. But it is also disingenuous, they say, because in most of the country at least, "simple people" still use the word.

Ok Socheat, the party spokesman for Funcinpec, does not understand the confusion.

"It's a word created by the CPP when the Vietnamese arrived in Cambodia in 1979," he says. "They would like to change the story."

The CPP says it has renounced all use of the word because is unacceptable in political discussion.

"We never use it in official speech," says General Khieu Sopheak, spokesman for the Ministry of Interior (MoI) and a CPP member. "I don't think it's a racist word as it has been spoken by our ancestors for a long time."

That is how many politicians end up defending use of the term.

"It's a problem if you're building a liberal democracy and scapegoating one part of the population," says Dominic Cardy of the National Democratic Institute. "You could also argue that [politicians] are doing it for election reasons ... all the more reason for liberally-minded people not to use it in an election. Unfortunately, the leader of the opposition party has used it a lot."

Rainsy has been at the heart of the controversy, but says he has not received complaints from Vietnamese over his prolific use of the word. He acknowledges it can offend, but says that "depends on tone and circumstance", and can also be seen as "totally neutral". But he admits he has begun to rethink his use of yuon.

"I try to pay attention to concerns raised by the word in some circumstances," he says. "Now I use Vietnamese and yuon indifferently."

However, Rainsy maintains that charges of racism are unfounded. Ultimately, he says, he wants to ensure peace, and that all communities can live in peace.

"My vision for the future is of our nations to be like the EU, " he says. "We are former enemies that become best allies working for common prosperity."

When asked about violence resulting from the use of the word, he retorts that such accounts can be deceiving: "Be careful. Things can be presented in such a way that serve the political interests of some special group."