At irregular intervals over the past 8 1/2 months, a small club of 16 of the nation's top corporate and Labor leaders has been meeting here secretly to try to hammer out private "understandings" on a spate of key economic issues.

The sessions, held in a rented room at Washington's posh Hay-Adams hotel, often are attended by high Carter administration economic officials. The three sides spend most of the afternoon and early evening together and then quietly adjorn. There are no public announcements of what they accomplish.

There's nothing sinster about such sessions. On the contrary, for all its attempts to keep a low profile, the labor-Management Group, as the informal panel is known, is a key element in the Carter administration's long-range anti-inflation policy.

In a lengthy anti-inflation statement last April 15, the President hinted he would count on the panel to develop what the White House could not put together on its own - a credible long-term program for gradual restraint of wage and price increases.

The difficulty is, after almost nine months of on-and-off negotiations, the venture is going at what all sides consider a snail's pace. Although the group has made progress on some specific issues involving health and illegal alien legislation, it has yet to come to grips with any serious plan to deal with wage and price restraint.

Moreover, many insiders familiar with the panel's negotiations say it's highly unlikely any such proposal will emerge in the forseeable future. "There hasn't been a great deal happening here," says one key official involved in the group's deliberations." And I think it's safe to say that whatever finally emerges is going to take some time. Months certainly, and maybe even years."

The holdup is important because, in one sense at least, the outside-the-government Labor-Management Group may be the administration's only real hope for mounting a meaningful long-range fight against inflation.

Although the White House has revived the long-dormant Council on Wage and Price Stability, the official administration inflation-watchdog agency is expected to confine its efforts to averting potential trouble spots in key industries. And sideline wage-price efforts launched by F. Ray Marshall, the Secretary of Labor, are not being taken seriously downtown.

More important, the Labor-Management panel's effort goes more to the heart of what the White House is trying to accomplish. Even before last January's inauguration, top Carter economic advisers seriously habored notions of trying to establish a sort of European-style "social contract" with business and labor in which the private sector would agree voluntarily to abide by a set of government-drafted wage-price guidelines. Partly because of administration bumbling, the guidelines plan has collapsed. But the social compact idea remains.

To be sure, the notion of setting up a tripartite business-labor-government panel to work out economic problems privately has not been unique to the current administration. Such panels have existed for years, under both Democrats and Republicans.

In the Nixon administration, for example, a quasi-official group comprising many of the same members of the present panel was able to hammer out important agreements on inflation-cutting practices in a number of key industries. In the Ford administration, business and labor members even agreed on a joint proposal to boost the investment tax credit for corporations.

"But this time the atmosphere is different," says one observer close to the present panel's deliberations. For one thing, both the business and labor members openly distrust the Carter administration, and are wary of committing themselves to considering long-term anti-inflation plans, insiders report.

For another, both sides are adamantly against any form of wage-price restraints, voluntary or mandatory - and that includes guidelines or any other measures designed to inhibit wage or price increases.

(The White House found that out, rudely, last spring when it naively suggested that companies and unions notify the administration in advance of coming wage or price boosts. The resulting storm was so fierce that policy makers were forced to back down within days after their trial balloon was launched.)

Finally, although the administration still hopes the Labor-Management Group will come up with its own solution for the nation's inflation problem, the panel's members are looking to the government to suggest something - and here the administration has done virtually nothing.

"The ball has been in the government's court since last April," grumbles John T. Dunlop, the crusty Harvard University economist (and former Ford administration labor secretary) who established the group several months ago and later cajoled panel members into serving as an unofficial White House advisory arm.

But Carter administration officials concede they've had little themselves to throw on the table. "The government's not too clear itself what we should propose," says one senior policy maker close to the negotiations. "We really have had no specific proposals to discuss."

As a result, the labor and management representatives on the panel have gone ahead on their own, dealing mostly with narrower issues with far fewer implications than the broad questions of industrial pricing and collective bargaining that the administration wants to talk about.

The results here have been mixed: Earlier this year, the panel came up with its own energy program, but the package was virtually ignored by the White House. Later, the group agreed to pledge its cooperation on a tough crackdown on illegal aliens, but here, too, the administration spurned its key proposals.

In the meantime, panel members have worked quietly away on their own agenda of individual proposals that require no government approval to carry out - including suggestions involving medical care costs, transportation, food and investment in new plant and equipment.

Although the sessions with government officials have been uniformly cordial, the White House annoyed the panel almost from the start by misstating its goals for winding inflation down. The group had suggested a target of shaving a half percentage-point a year from the present 6 per cent pace - to a low of 4 per cent by 1960. But Carter, in his speech announcing the move, mentioned only the final objective - and provided no hint at all on how he planned to accomplish it.

Indeed for their part, the business and labor representatives have never let the goverment forget that despite its White House backing the panel still is a private - not an administration - institution.

Typically the 16 "regulars" assemble about 2 p.m. and hash over their own agenda before the Carter officials are scheduled to arrive. The government representatives usually come in about 4:30, and the talks go on through 6, when the session breaks for drinks and dinner. The meeting almost always are over by 7:30 p.m.

Apart from Dunlop, the regulars include Reginald H. Jones, chairman of the board of the General Electric Co; George Meany, president of the AFL-CIO-Meany's heir-apparent, AFL-CIO treasurer Lane Kirkland; and Walter B. Wriston, chairman of Citicorp.

For the government, the delegation includes Schultze; Marshall; W. Michael Blumenthal, the Secretary of the Treasury; Juanita M. Kreps, Secretary of Commerce; and Barry Bosworth, director of the wage-price council. Sometimes the full meeting is called off so the time can be used by individual subcommittees.

Unlike the pattern in some previous panels, President Carter never has attended - an absence that irks some panel members.

The agenda for the group's next meeting, now scheduled for Oct. 17, included two relatively weighty topics for any such gathering - how to spur lagging business confidence, and what to do about the worrisome excess capacity that still exists in many industries, especially steel. Both are of key concern to the administration.

As for fighting inflation, however, insiders are pessimistic that the panel will move anytime soon to work out a full-fledged wage-price policy. Committee members dispute recent reports that the panel is on the verge of any new breadthrough. "If it's going to be resolved at all, it probably will take several years," one strategist says.

Meanwhile, one of the administration's potentially most promising tools for forging a long-range anti-inflation policy is languishing unused. And the President's heady promise of last April to develop a comprehensive price-stabilization program is no more fulfilled than it was last spring.