Gloria Gaynor, the notarized queen of disco (her "I Will Survive" simultaneously No. 1 in the United States, England, Canada and New Zealand), was taking the night off: no singing, no jiggling.

The party at Washington's Mazza Gallerie was going on without her, but Gaynor didn't mind. For once she could sit down, away from the dance floor, in modest black crepe and chiffon. She could sip her white wine and survey the scene instead of sweating in Lycra jeans and sequinned top and singing on a mirrored bandstand to a field of turnedon, glittered-up dancers.

"This is important for me, just mixing with folks," Gaynor said, greeting admirers with a cheery economy of words. "I'm essentially a people person. Right now I can't do enough for people who have helped me."

For her own survival, Gaynor is keeping it cool. Eight years into her career, she already has been part of several disco syndromes-the overnight success, the slip into near obscurity, the exciting comeback. Noew she's balancing the demands: be tough enough to survive; be soft enough to communicate.

What she wants in this disco cycle, with its thundering beat, is an enshrinement of her lyrics rather than her hips.

The result is a mellow, almost spiritual disco personality. Gaynor has a wide, pretty face framed by tight curls, and her glossy brown eyes are accented by theatrical lashes. On stage, Gaynor has another image: that of the ladylike strip-teaser.

"My image is me. When I am in a restaurant and someone recognizes me, I don't have to perk up. I'm up," said Gaynor, as the disco party swirled through the four-level mall around her.

The night off was also giving her batteries a chance to recharge for the remainder of her grueling 48-city tour. "I Will Survive" preceeds her everywhere she goes on the road.

"In each place you find similar responses. Besides the full houses, I mean the conversations. People come up and talk about their Gaynor record collections-all six albums. Someone at the airport today said, 'I have all your records back to Honey Bee.' That's only 1973," said Gaynor, laughing somewhat at the intensity of her fans. "Then I get teen-agers who have thought of dropping out of school or giving up, and my song 'Survive' has made them reconsider. Lately I get a lot of guys who come up and say "My lady plays Survive all the time, and asks if I'm getting the message.' All I can say is 'I hope you are getting your act together, because women know how to survive.'"

There's a story behind "Survive's" ardent declaration of a woman's determination to overcome life's setbacks. And it's more than the fact that Gaynor, in her 30-some years, has been burned a few times.

Two years ago, while singing at the Disco Oscars, she fell and ruptured a disc. "I had a six-hour bone graft and spinal fusion operation. Now, I'm not saying I was thinking of a song then, but the night before the operation my aunt called and said, 'I know you are trying to be brave, I know you feel it's hopeless.' And I said, 'It's not hopeless, and I'm not going to be bogged down in self-pity,'" says Gaynor, recounting her own feelings unemotionally.

After a recuperative period that coincided with Donna Summer's near-monopoly of the sultry disco image, Gaynor returned to the studio. She needed a hit.

"I went to do another song and 'Survive' was the B side. I knew it was more Gloria Gaynor. I felt it; it triggered a personal involvement, a personal emotion.I prayed that the other side wouldn't make it," she recalled.

"Survive" touched all the right chords, becoming a blockbuster pop and disco hit. It pushed Gaynor onto Rolling Stone magazine's chart of the top 30 prime movers in disco, nudged Rod Stewart's "Do Ya Think I'm Sexy" down to second on the charts, and prompted Regine to record it in French, so that all Paris is now singing "Je Survivrai."

This is the kind of success kids from Newark, N.J., only dream of Especially when they haven't any musical entree, such as the church provided other Newarkers, Melba Moore and Dionne Warwick.

"I used to listen to all the popular songs and would sing along," Gaynor said. "Frankie Lyman pushed me to a career. I would listen to his "Why Do Fools Fall In Love?' and I sounded like him, so I decided to sing."

She was one of seven youngsters. Her father, a vaudeville entertainer, had a desk job at the fire department, and her mother was a seamstress.

After her discovery in a night club, she never took vocal lessons because of money restrictions, and was plowing the long, ardous road until she and disco crossed paths.

In 1974 she made her disco mark with the first album especially producted for non-stop dancing-three cuts without grooves. Within a year the National Association of Discotheque Disc Jockeys had elected her "Queen of the Discos."

When she talks about disco's apparent entrenchment, Gaynor prefers to discuss the sociological causes and effects. "Music changes in response to a social change. Disco responded to an economic strain; people needed an outlet," said Gaynor. "Now, as anxieties have worn off, the music has slowed down, the dances have been altering, the music is being more melodic. Disco is here to stay; it's a world culture.

It's competitive world, but Gaynor sees her own specialness as a key to longevity. "Being called a disco singer doesn't limit me at all. It does have a small definition, but I try to reach for lyrics that will last," she says.

Does she think Donna Summer has the same staying power?

She skips that. "When people compare us, I figure they like us both or hat us both, so we are even. I don't think her success has harmed me. If I were in competiton with her in my own mind, then I would only be looking back. I am going forward."

Then, smugly: "And since I am not a sex symbol, I don't have to worry about losing lots of fan when I'm not sexy anymore." CAPTION: Picture, Gloria Gaynor, by John McDonnell-The Washington Post