(CNN) President-elect Donald Trump's selection of Stephen Bannon as his chief strategist and senior counselor swept a new term out of the fringes and into the mainstream: white nationalism.

So, what exactly is "white nationalism"? Activists on the front lines of fighting racism say it denotes white domination and superiority.

Promoting the interest of whites

Oren Segal, director of the Anti-Defamation League Center on Extremism, said white nationalism is a term for a form of white supremacy or separatism.

Its supporters defend "country by white racial identity." They promote the interests of whites exclusively and denigrate all others.

"Bannon established himself as the chief curator of news for the alt-right," he said. "And when you descrbe Breibart as a platform for the alt-right that's not insignificant."

"Under his stewardship, Breitbart emerged as a leading source for the extreme views of a vocal minority who peddle bigotry and hate."

White domination

Mark Potok, senior fellow at the Southern Poverty Law Center, said the term white nationalism means white domination. It isn't necessarily an endorsement of a 100% pure white society, a goal now regarded by the far right as unrealistic, he said.

"White nationalism is more the idea that whites should dominate," he said, that the culture should dominate and policies that jibe with the idea should be supported, such as opposing nonwhite immigration.

White nationalists believe the country "should be built by and for white people." They "tend to be less about ethnic slurs, less about Nazi slurs, tend to speak more academic language."

Some people who embrace the white nationalist identity refer to themselves as "race realists" -- generally speaking, that means people who believe the races can't live together. They may also call themselves " Identitarians ," a movement that emerged last decade on the French far right. The movement is linked to the opposition to multiculturalism and anti-Islam attitudes.

'The people I'm describing don't live in Washington'

Paul Gottfried is the former Horace Raffensperger professor of humanities at Elizabethtown College in Pennsylvania. He is also the president of the H.L. Mencken Club, which calls itself a "society for the independent right."

He said "white nationalism is more often used by the left than on the alternative right" and that "white Identitarian" and "race realist" are the terms more common on the alt-right

Gottfried rejected the view that Bannon i s a racist, an anti-Semite, a white Identitarian or race realist. Instead, Gottfried said, Bannon comes from the world of Washington politics and journalism.

"The people I'm describing don't live in Washington," he said, when making reference to race realists and Identitarians. "I don't think he knows any of those people."

'I like the term alt-right'

A major voice of the alt-right is Richard Spencer, president of the National Policy Institute and the editor of Radix Journal. He defines " white nationalism " as a U.S.-focused movement concerning white racial consciousness and identity.

"I don't use the term white nationalist to describe myself," he said. "I understand it's a fairly fair term. Obviously white refers to race, of European descent."

To the extent that nationalism means caring for one's family, that is a good thing, he said.

But the word "nationalism" reflects deep-seated historical grudges, "ethno-nationalism," in which Europeans warred with one another.

"We want to get beyond these things," Spencer said. "I like the term alt-right. It has an openness to it. And immediately understandable. We're coming from a new perspective."

He prefers the terms Identitarian and alt-right.

Alt-right, he said, "has a new starting point from conventional conservative. That was the origin of it."

"It's been filled out and come into its own. It's an Identitarian movement. Race realism is a component of it. It's an understanding of European identity ."

Distancing themselves from white supremacy

Daryl Johnson is the owner of DT Analytics, with DT standing for domestic terrorism. He is a security consultant and a former counterterrorism expert at the Department of Homeland Security.

White nationalism is a "new buzzword," Johnson said, but the first time he saw the term was in "white supremacy literature."

The far rightists used "white nationalism" to appear more credible and patriotic, Johnson said, and the term detracts from the stereotypes conjured by white supremacy.

But make no mistake, he argued, white nationalism is a euphemism. "They want to distance themselves from white supremacy," he said.