She's sporting a platinum coif and just a bit of a 'tude, a regal way of letting it be known when the lady is displeased. She's Mariza, lean of line, greyhound sleek and designer-clad, diamonds blinging on the hand clutching a Louis Vuitton bag. Mariza sells out concert halls around the world, as famous for her fabulous costumes as she is for that voice, a modern-day glamazon taking on Old World tunes. And because she's big news back home in Portugal, singing fado, the Portuguese blues, and her record label would like her to be even bigger news here, she is traveling with a bit of an entourage: publicist, manager/beau, label exec, all of whom hopped the Metroliner from New York to be here.

But let us be clear about one thing: The single-monikered Mariza, the woman poised to become the world's next great fadista, is not, not, not, not, not a diva.

"I am not," she sniffs over lunch. "I hate the word. Diva comes from the word divine, and I am not.

"I'm a regular person," adds Mariza, who says she's 32 (although reports vary), and whose third CD, "Transparente," will be released Tuesday. "A regular person who sings a different kind of music."

About that different kind of music: Mariza is a young woman singing music that has traditionally been seen as the province of mournful old ladies shrouded in black. With her designer duds and flair for the dramatic -- music videos, anyone? -- she's turned the melancholic image of fado inside out. But with "Transparente," she is expanding the boundaries of the music as well. (Mariza will perform at Lisner Auditorium on Oct. 6.)

Traditionalists sang preexisting poetry accompanied by the simple melodies of the 12-string guitarra portugesa. With "Transparente," recorded in Brazil with Grammy-winning producer Jacques Morelenbaum, Mariza tweaks tradition, collaborating with renowned Portuguese poets on lyrics and adding a flute, cello and accordion to the mix. And though fado uses no drums, subtle rhythms percolate throughout her album, more so than in her previous records, "Fado en Mim" and "Fado Curvo."

On these shores, she's lumped into the amorphous "world music" catalogue. It's not a term she's fond of. World music, she says in her charmingly eccentric English, is just a "name to construct a market." She prefers the term "cultural music" because that's what she's doing, singing the music of her culture. Fado, with all its poetry and its swooning melancholy, is the music of the people, the poor people's CNN; it's about giving and receiving, and as she sees it, a diva does not do that. Give and receive.

At the beginning of her career, fado was strictly an undercover thing. People of her generation associated it with the dictator Antonio de Oliveira Salazar's regime, which fell in 1974. Singing fado wasn't exactly cool. So she started out singing everything from bossa nova to funk -- even James Brown.

At this point, Joao Pedro Ruela, Mariza's partner in love and in music, chimes into the conversation.

"Mariza used to sing, 'Ooooooooh, I feel goooood,' " Ruela says, laughing as he mimics Brown.

"But then we discovered that fado was her music."

"I was so in love" with fado, Mariza adds. "So impassioned."

She is, she will tell you, the embodiment of the French word metis, or "mixed." Her Mozambican mother is a blend of indigenous African, Indian, French and Portuguese, while her Portugal-born father is of Portuguese, German and Spanish extraction. Mariza was born in Mozambique, but landed in Lisbon when she was 3. She's spent a lifetime with a foot in each world, feeling neither/nor, either and or.

Like her, she says, "fado is not pure music." It was born sometime in the 19th century, the result of an intermingling of cultural influences: homesick Portuguese sailors, even more homesick African slaves, along with Brazilians, Jews and Arab troubadours.

The title song of "Transparente," with poetry by Paulo Abreu Lima, was written with Mariza in mind, even though the poet didn't know the singer and knew only that she was born in Mozambique of mixed heritage. In it, Lima explores the connections between Mariza's birthplace and fado's African roots. It is, she says, at its essence, an autobiographical poem.

Between the earth and divine

My black grandmother knew

Those things about destiny . . .

I see a head of plaited hair

And the cradling song of the fado

In a shawl of curls . . .

The African drums are guitars

Performing last month at Live 8's "Eden Calling," the all-African concert produced by Peter Gabriel, was a chance to reconnect with her African side -- not to mention those African drums.

"I was feeling all these African people. I was feeling like, yeah, they are my people. I know exactly what they are doing, I know the rhythms, I know how to dance, I know the songs, I know what they're talking about. I was feeling like, 'Yeah, this is my world, too.' At the same time, when I'm in Portugal, I feel like, 'I'm Portuguese, this is my world, too.' "

Portugal was where her love for fado was born. Her family nestled into the old district of Mouraria in Lisbon, a neighborhood where fado held sway. It was there that they opened a taverna, a restaurant that was, she says, "not a fancy thing," a place where poor folks could grab a bit of soup, sip some wine, nosh on some bread with their last few pennies, and where people came to sing fado. They'd drink wine, and they'd sing way into the night. Five-year-old Mariza listened from the family's apartment above. Entranced by the guitars, the drama of it all, she decided that was what she, too, would do: Sing fado.

She says she didn't choose fado, it chose her, and she's been enslaved ever since. Not that she minds the enslavement.

Or perhaps it is she who is doing the enslaving.

"It's mine. It's mine. It belongs to me," she says emphatically, gesturing with her hands, her right-hand diamond flashing in the afternoon light. "My culture. My language. My people. I don't have to think. It's like breathing. It's like skin."

A star in Portugal, Mariza hopes listeners here will warm to fado, the melancholy genre she has championed in her homeland.Mariza prefers the label "cultural music" to "world music" because she sings the music of her Portuguese culture.