Vegetarianism may be coming of age in America, but vegetarian restaurants, in the Washington area at least, are still in their infancy. In the past year, however, more than four vegetarian restaurants have sprouted up, joining a handful of establishments already catering to non-meat eaters.

You won't come upon these restaurants in dining-out listings. They don't advertise much, are relatively difficult to find and rely on the vegetarian underground to pass the world around. But the interest in alternative eating styles in such that the Food Section determined to visit the restaurants, examine them and sample the foods they prepare.

A problem that comes up even before choosing where to eat is defining the word "vegetarian." It's more than just not eating meat. Some turn to the diet as an alternative to eating chemical-laden processed foods. Others become vegetarians for religious reasons, and still others for ethical reasons.

If you eat dairy products, eggs and cheese you are a "lacto-ovo" vegetarian. If you eat only fruits, vegetables and grains, you are a "vegan." If your diet consists of nothing but fruit, it's "fruitarian."

The restaurants themselves are as diverse as traditional ones, with prices that vary considerably. The menus illustrate a fair sampling of the variety and imagination vegetarian cooking has to offer, although quality is inconsistent.

Two Indian restaurants offer ethnically accurate, eye-watering curries and savory snacks, as well as hot teas and lassi , a cold fruit drink. The others feature salads, in which tomatoes, avacados and alfalfa sprouts (the french fries of vegetarian cuisine) are the main attractions. Soups are hearty and often serve as an entire meal. Breads, in some cases baked on the premises, are made from whole grains.

Hot entrees may include sauteed mixed vegetables served other steamed brown rice, vegetable quiches, pasta and meatless enchiladas. Large and small portions usually are available, so the diner can order as much (a dinner) or as little (an appetizer) as desired.

With one or two exceptions, vegetarian restaurants here are small, clean and attractive. Usually there is no tipping and no smoking. The clientele, managers say, is more than 75 per cent nonvegetarian.

Alternatives to strictly vegetarian places are semi-vegetarian restaurants (see a list accompanying this article) and the numerous Oriental restaurants - Japanese, Chinese, Thai, Vietnamese and others - that offer skillfully prepared vegetable dishes. Most restaurants serving meat also will provide an all-vegetable plate on request.

Those seeking a totally vegetarian meal at a semi-vegetarian restaurant should ask if the soup stock is made with meat, if there are eggs in the ice cream or if animal fat is used in frying.

The biggest problem in running a vegetarian restaurant appears to be finding good, experienced cooks. Most do not seem to have acquired sufficient skill in the use of seasonings, the spices and herbs intended to perk up the flavor of many vegetarian dishes. Another problem is the soaring cost of fresh fruits and vegetables. One restaurant reported its weekly vegetable bill had gone from $100 to $400 in just two years.

At this time, there is only one "full service" vegetarian restaurant, the Golden Temple on Connecticut Avenue just north of Dupont Circle. The only fully organic restaurant is the Berwyn Cafe in College Park. The service in both can most generously be described as relaxed. The others all are cafeteria-style operations.

Here are descriptions of 10 restaurants and some of the items on their menus.

Gate Soup Kitchen 3338 M St. NW (337-2637). Open 7 days a week 11:30 a.m.-11:30 p.m. Gate Soup is in its fifth year as a vegetarian food operation and is a simple, clean and airy setting for some fine, painstakingly prepared food. Soups, salads and sandwiches are made fresh daily with plenty of seasonings and a concern for what is attractive on the pllate as well as pleasing to the palate. A good example is the Fruit Delight ($3.75), a salad of fresh blueberries, melon, pineapple, banana, walnuts, grapes, orange and coconut. It is served with a side order of plain or frozen yogurt. The Garden Sandwich ($2.25), a mass of avocado, tomatoes, scallions, mushrooms, sprouts and garlic mayonnaise piled between two slices of 7-grain bread is good, but messy. It might better be eaten as a salad, with bread on the side - an option offered on the menu. The House Pate ($2.35) is an interesting spread based on lentil beans and served with a bed of sprouts and house dressing. As might be guessed from the restaurant's name, the soups are real winners. A small sampler of four soups (which change daily) is $2.75. Individually, soups are $2.25 for a large bowl and $1.55 for small. The Gate Soup Kitchen is planning to expand its operation and to include a health food and produce store.

Golden Temple of Conscious Cookery 1521 Connecticut Ave. NW (234-6134). Open Mon-Thur. 11:30 a.m.-3:30 p.m. and 5:30 p.m.-10 p.m. Sat. noon-3:30 p.m. and 5:30 p.m.-10 p.m. Closed Sunday. The Golden Temple, also in its fifth year of operation, is run by members of the Sikh Dharma 3-HO Foundation. The California-style restaurant, with blond wood and hanging plants, has an attractive dining room with a small health food store in the front. Vendors sell the Golden Temple's food downtown, and the staff provides vegetarian cooking lessons and a catering service. A spinoff, The Golden Temple Emporium in Georgetown, is a retail health food store which also sells sandwiches and beverages.

Among the Golden Temple's specialities are a superb East Indian curry, a vegetable dish of peas and potatoes in a spicy curry sauce served over Basmatti rice and accompanied by dollops of raisin chutney and yogurt. It comes a la carte ($4.80) or as a dinner with soup, salad and muffin ($5.50). Despite flaws - mushrooms can be gritty, or wilted lettuce as the base for an imaginative salad - The Golden Temple is a fine place to dine, although its prices are high.

Premlata Three locations: 7315 Wisconsin Ave. (654-4515), Bethesda Square and Rockville Mall. Open weekdays 8 a.m.-6 p.m., Sat. 9 a.m.-4 p.m. Closed Sunday, Premlata (which means "vine of love") is the local McDonald's of vegetarian food. Sandwiches, salads and juices are served up with skill and speed and the prices are reasonable, if not downright cheap. Farouk Gongee and his wife Sally started the operation last year, and have expanded to three locations. A fourth, called "Health's A Poppin" is set to open at 20th & K this summer. The Fuzzbee ("over 35,000 sold") was a winner in the sandwich category.The combination of cheese, lettuce, tomato, sprouts, in pita bread is enhanced by a spicy spread of curry and other seasonings. At $1.45, it is the best buy. Also high on the list is the Super Salad ($1.75), a mound of feta and Muenster cheeses on a bed of greens accompanied by tomato, cucumber, sprouts, avocado, carrot and green pepper. There is a tasty miso dressing.

Siddhartha 1412 New York Ave. NW (638-6828). Open daily 11 a.m. to 9 p.m. One of two all-vegetarian Indian restaurants in Washington, Siddhartha opened two years ago on the sight of a fast-food eatery and decided to keep the operation as such. We tasted the Cauliflower Curry ($3.50), which comes complete with pulao (rice), two poories (puffed, deep-fried bread), hot pickle, papad (like a tortilla), chutney and raita (yogurt). The curry was spicy and good, but the rice contained what looked like frozen mixed vegetables. The Broccoli Special was a mix of sauteed broccoli and spices (tamarind and tumeric) also served with the above. Samosas ($.70 for two), savory snacks of peas and potatoes and wrapped in dough and deep fried, were given high marks. Also popular was the chivda ($.60), a dry snack of flat rice, peanuts and raisins. The restaurant itself is cool and dark, with Indian music on the jukebox. One jarring note is a soft drink dispenser on the counter.

The Berwyn Cafe 5010 Berwyn Rd. College Park (345-2121). Open noon-8 p.m. Tues.-Sat. Closed Sun. and Mon. The Berwyn Cafe, founded in 1973, is the only organic vegetarian restaurant in the Washington area and devotees swear by it. It's located in a dilapidated building and the atmosphere is definitely late 1960's hippie-style, with the kitchen and part of the dining area sharing the same room. One almost expects to see an old mattress of two lying around. But around the corner is a lovely Japanese-style dining area, with low wooden tables and fat pillows. The Berwyn Special Sandwich ($1.50) is the winner here, one of the best vegetarian sandwiches available in the area. It is a combination of cheese, tomato and sprouts on the Berwyn's freshly baked bread. The specials, which change daily, may include a flavorful mix of sauteed vegetables with cream sauce and rice ($1.75) which was rated as very good. Prices are low.

Yes! 1039 31st St. NW (338-6950). Open 11 a.m. to 9 p.m. Tues.-Sun. Closed Monday. Yes! is the oldest vegetarian restaurant in Washington (founded in 1970) but has been slipping in the past few years. The menu is not as varied as some of the more recent competitors, and the quality of the food is down. However, the restaurant is expanding into a full-service operation when the health food store, presently located in the front room, moves to a new location this summer. We tried the sauteed vegetables with brown rice ($2 a la carte, $3.25 dinner) and found the vegetables perfectly cooked, but underseasoned. The Yes Sandwich ($2.50) is a meal in itself. It includes cheese, sprouts, tomato and lettuce on whole grain bread, but the macrobiotic bread was dry and tasteless. Yes! also serves beverages and desserts and offers seating on an outdoor patio.

Paru's 2010 S St. NW (483-5133). Open Tues.-Sun. 9 a.m. to 8 p.m. Run by an Indian family, Paru's opened last year and is still having growing pains. The food is spicy and varied, if a bit overpriced. The special of the day, masala dosai ($2.50) a pancake of grated rice and curry filling fried in ghee (clarified butter) could have used more filling. The coconut chutney was a nice touch as was the spicy sambar. The vegetable curry was properly spiced, the rice fluffy, and the stuffed parotta ($2.25), a potato curry between two rounds of parotta dough, was flavorful. The samosas, deep-fried potato curry, were freshly made but too doughy. There is a sign on the wall that reads "Food mostly cooked to order. Waiting necessary will be rewarding."

The Body Shop The Eatery, White Flint Mall, Rockville. Open Mon. through Fri. 11 a.m.-10 p.m., Fri. and Sat. till midnight, Sun. noon-7 p.m. This vegetarian booth is reportedly the most popular among the 12 fastfood outlets that comprise The Eatery complex. There are eight major items - salads, hot entrees, such as a vegeburger ($1.25) and casseroles - and beverages are served. The smoothie, a chilled yogurt and fruit drink, is much in demand. It costs 75 cents.

The Store Next Store 4949 Bethesda Ave., Bethesda Md. (986-0848). Open Tues-Sat. 10 a.m. to 3 p.m. Closed Sun. and Mon. Run by the Bethesda Co-Op, The Store Next Store is the most recent vegetarian restaurant in the area and still has a way to go. They offer soups, sandwiches in pita bread and salads. Open for lunch only, the restaurant is still in the barewall stage. But the prices are reasonable (soups $.50 with wheat muffin, sandwiches $1.05, tabbouli salad $.50) and the specials change daily.

Columbia Union College Cafeteria & Snack Bar Flower and Carroll Ave., Takoma Park (270-4984). Call for summer hours. The vegetarian food we tasted from the snack bar and cafeteria of this Seventh Day Adventist-run college included textured vegetable protein shaped into forms resumbling slices of chicken, beef and ham for hoagies ($.80), mock chicken salad, ($.80). Mock scallops and turkey for hot entrees ($2.25) were topped with a glue-like mock chicken gravy. Mushy frozen peas and instant mashed potatoes accompanied the dish. The Winners: The Best Vegetarian Dishes

Fruit Delight (Gate Soup Kitchen)

Raisin Chutney (Golden Temple)

Fuzzbee (Premlata)

Samosas (Siddhartha)

Vegetable Curry (Golden Temple)

7-Gain Bread (Gate Soup Kitchen)

Misco dressing (Yes!)

Gazpacho Soup (Gate Soup Kitchen)

Berwyn Special Sandwich (Berwyn Cafe)

Stuffed Paratta (Paru's) The Semi-Vegetarian Restaurant Scene

Washington

Food For Thought

Nature's Way

The Greenery

The Paradise Cafe

Ginseng Tea House

Marigold's

Columbia Station

THe Apple Tree

The Potter's House

Sunlight Fare

Virginia

Mother Nature

40 Carrots - Bloomingdale's

Grass Roots

Maryland

40 Carrots - Bloomingdale's

G.D. Graffiti