At Kilimanjaro, one of Washington's newest nightclubs, the ambiance is of Africa. Tribal masks, zebra skins and the head of an ibex hang on the walls, and patrons sip their drinks under the circular bar's thatched roof.

The club, named for the snow-covered mountain that rises in East Africa, is owned by Kenyan Victor Kibunja, who also owns the Amboseli Foreign Car Repair shop nearby on Florida Avenue in Adams-Morgan and has lived in Washington for 14 years.

Kibunja's transition from visiting student to resident businessman is indicative of the fact that more and more Africans, most of whom come here to go to school, appear to be staying longer in Washington and are beginning to coalesce into a recognizable community.

"Those who are saying, 'I'm going home immediately' are disappearing," said Gideon Kioko, a Kenyan who has been in the United States for 20 years and is now chief of obstetrics at Columbia Hospital for Woman. "There is certainly a budding population of Africans who are permanent here . . . . There is a community one can talk about now."

Africans are not alone in making this shift toward a semipermanent community in Washington, but they are a good example of a worldwide phenomenon, the so-called "brain drain" that has seen the educated and entrepreneurial elite of developing countries in the Third World migrate, for a time at least, to the greener pastures of the industrialized countries, pulled by a higher standard of living and pushed by limited opportunities at home.

Exact numbers are difficult to obtain, but it is apparent that the African population in and around Washington has grown in the last decade, swelled particularly by Ethiopians who have flocked here since a Marxist government replaced the rule of the late Emperor Haile Selassie.

Kibunja, for example, says that when he came here in 1967 to study mechanical engineering there were "give or take 40" Kenyans in the area and he knew them all. The Kenyan embassy now estimates there are about 400 Kenyan nationals in the area. Howard University has the largest African student enrollment -- 960 -- in the country.

Any regular cab user in Washington has noticed the increasing number of Ethiopian and Nigerian taxi drivers. And a men's clothing store at Prince George's Plaza has begun accepting Nigerian currency as well as U.S. dollars because so many of its customers are African. Prince George's County has become one of the popular places for Africans to live, along with the Columbia Road and 16th Street areas of Northwest Washington.

Recently, the first two professional organizations for Africans in the area were formed.

The International African Lawyers Association is temporarily headquartered in the Southeast Washington home of its president, 30-year-old Marazere Ubani, who graduated from Howard University's law school last year.

The 7-month-old group has about 30 members, according to Ubani, who is Nigerian. It was formed to foster academic and social interchange among African lawyers in the U.S. and Africa, to make legal counsel available to fellow Africans here, and to organize exchange visits between African lawyers and their overseas counterparts, Ubani said.

"More Africans are coming into this area and settling more permanently than before because of universities and embassies," said the association's secretary, Raymond B. Thompson of Sierra Leone, another Howard law school graduate who has been in this country 14 years. "We wanted them to know there are African attorneys in the area who are willing and able to help in immigration law, and criminal and civil matters."

While stressing that their group is not a political one, Thompson says it intends to be a voice on African issues both in Washington and with African governments.

Last year saw the birth here of the Association of African Physicians of North America (AAPNA), which now has about 100 members, according to its chairman, Dr. Carl Reindorf of Ghana, who is clinical associate professor of pediatrics and child health at Howard University and a staff physician for the university's sickle cell disease research unit.

Reindorf said that besides providing social and professional contacts for African physicians and dentists in this country, AAPNA will work to sensitize both Africans and Americans to the health needs of Africa, encourage Africans to return home to work, and act as a liaison between Africa-based medical groups and international agencies based in the U.S. such as the World Health Organization.

Like the lawyers' group, AAPNA also is designed to evenutally gain enough clout to lobby effectively with Africans governments to make health care more of a priority than it is now. "We want to have a lobbying group cutting across the national barriers [of Africa]," said AAPNA president Nkwachukwu M. Adiele.

The formation of these groups raises the question of whether they might actually encourage the brain drain. The absence of skilled technicians, educators and businessmen is often cited by governments in Africa and officials here as one of the severest handicaps to economic progress on a continent that has some of the poorest countries in the world.

The number of African students in the U.S. has risen from 1,231 in 1955, before most African countries were independent, to 29,560 in 1977, or 12 percent of the foreign student population here in that year, according to the Institute of International Education.

One recent academic study estimated that 12 percent of those students stay on for some time after completing their studies. The U.S. and several European governments so worry about that figure that they recently set up a $3 million program to encourage Africans to return home.

The project, called Return of Talent, is run by the Intergovernmental Committee on Migration, a joint venture of the U.S. and the European Economic Community countries. Over the next two years the ICM hopes to help 200 Africans and their families living here and in Europe return to Africa, said Gretchen S. Brainerd, ICM's Washington representative.

The ICM, which has run a similar program to help Latin Americans return to their countries from Europe since 1974, will help Africans pay their air fares and the costs of shipping family goods home. If necessary, it will pay a wage subsidy for two years to cushion the economic hardship a returnee often faces in going to a lower paying job back home.

For many Africans, the brain drain is a sensitive topic. "I feel every African living in the U.S. who has some degree of talent has some degree of guilt," said Kioko, who goes home to work part of each year through a program run by Johns Hopkins University. "I've never met an African who says, 'I am never going home.' "

Some others disagree. "There is no guilt at all here," said AAPNA's Reindorf. "But people like you feel that we should be guilty. . . . True, the need is greater in Africa, but what is not clear is that the majority of our members are really going home to Africa."

Akhigbe Erumsele, a Nigerian who has been in the U.S. 16 years and is assistant to the dean of the College of Life Sciences at the University of the District of Columbia, said, "I've always taken the stand that the brain drain is not . . . that trained Africans are staying abroad, as much as there are no facilities, no institutions to use them even if they go home."

Said Kioko: "There is a certain amount of helplessness about whether or not the system in Africa will actually let them help. The system defeats you . . . . People feel they will not be able to participate in the process of changing the system. You go home, you open your mouth and you could end up in jail."

In addition, there is the higher U.S. standard of living. "They look at the relative standard of living; they get used to this standard of living, and they don't want to change," Kioko said.

Kibunja said he returned home to Kenya twice, in 1974 and 1981, to try to set up a business there. But he was frustrated by difficulties in obtaining financing, so he returned here and in 1975 opened his auto repair shop with the help of a Small Business Administration loan. Two months ago, he launched his new club, Kilimanjaro.

The brain drain from Kenya "hurts me. I worry about it," said Kibunja. "I do plan to go home and retire. If I had enough guts I would move now. But after 15 years in this society, you got so much financially involved in this society it would be hard to pack up and leave. I have 30 people of whom eight are Kenyan on my payroll. I could not just walk out on these people."

Said Erumsele, "The longer you stay abroad, the fiercer are the pressures to come home in style. The expectations of people at home increase. You don't want to come home with nothing. You stay to build up."