Virginia Knauer, special adviser to President Reagan for consumer affairs, has her own definitions for nine common phrases used in the marketplace. She calls the terms "Consumer English" and says that they can "spell lifelong protection in the marketplace" for consumers who understand what they mean.

For Washington area residents, who have been hit in recent weeks by problems ranging from the shutdown of health and fitness clubs to automobile advertisements promising "free air conditioning," Knauer's translations are especially useful.

Consider the "lifetime memberships" that thousands of area residents purchased from dozens of local exercise clubs. When the clubs collapsed, the "lifetime members" lost more than $1 million, according to estimates by consumer officials.

In her consumer dictionary, Knauer offers this definition for "lifetime" guarantees and memberships: "Whose lifetime? Yours or that of the product or the club ?"

Knauer also has some words of caution about the use of the word "free." Interpret it as "beware," she said. "You usually end up paying for free items in one way or another."

Montgomery County consumer officials agree. "We have had a number of complaints recently about automobile advertisements that offered free air conditioning," said Judy Doctor, an assistant to consumer director Barbara Gregg. "But the cost actually had been added in to the total price so that consumers really were paying for the air conditioning."

Here are the other phrases as defined by Knauer:

* "Only a few cents a week." More expensive than it seems.

* "Sale." Question it. Some stores have endless fire sales or closing out sales that are simply promotions at regular prices.

* "Just sign here." Stop immediately and read. You may be signing a binding contract.

* "Charity." Check it out. Is it a legitimate charity? Query the Better Business Bureau or your local consumer agency.

* "Secret cure or remedy." Could mean quack. Also, you should ask your doctor. Such claims are almost always false, and use of a "secret" product or treatment may delay legitimate treatment and lead to dire consequences.

* "You wouldn't like the advertised product. Let me show you something better." This may be bait-and-switch advertising. It's illegal but some stores practice it anyway.

* "Natural." Frequently means "more expensive" without any value beyond that of similar products processed differently.

When cooked ground beef is left unrefrigerated overnight, is it still safe to eat? What is the safest way to cook and store chicken salad ahead of time for a large party? The electricity went off for four hours last night, and I have $100 worth of meat in my freezer. Do you think it's spoiled?

Answers to those and other similar questions are available from the meat and poultry hotline operated by the U.S. Agriculture Department's Food Safety and Inspection Service, which provides information and takes complaints about the wholesomeness, labeling and safe handling of meat and poultry products.

The hotline number--472-4485--operates from 8 a.m. to 5 p.m. weekdays. At other times, an answering machine records messages. If you must call long-distance to reach the hotline, you can minimize cost by leaving your name and number with the hotline operator. Someone will then call you back.

If you have the time and would prefer an answer in writing, direct your question to the Meat and Poultry Hotline, USDA, Washington D.C., 20250.

Meantime, here are the answers to the questions above: No, the cooked ground beef wouldn't be safe to eat if left out of the refrigerator overnight. The best way to make chicken salad ahead of time is to cook the chicken in advance and store it in the refrigerator; then just before serving time, mix the chicken with the other ingredients.

Whether the freezer meat spoiled would depend on several factors--the freezer temperature, the meat packaging and whether the door was kept shut while the power was off.