Prime Minister P.W. Botha has added a new term to the vocabulary of South Africa's ruling National Party: ''healthy power sharing.''
But whether it means that this country is moving toward significant changes in its racial separation (apartheid) policies is much less clear. Two immediate snags stand out:
* The term power sharing has limited scope. It refers only to South Africa's whites extending some form of political representation, still undefined, to Indian and Coloreds (persons of mixed descent). Blacks, representing some 70 percent of the population, are not part of the discussion.
* The very process of trying to introduce the concept has produced one of the most serious splits that the National Party has seen during its 34-year of uninterrupted rule here.
Mr. Botha won an important confrontation with the arch conservatives of the National Party - a confrontation that has been simering in the background for some time and to some extend hampered Mr. Botha's ''reformist'' policies.
Earlier last week some National Party members of Parliament, led by Andries Treurnicht, refused to go along with a motion of support for the prime minister at a caucus meeting because of his power-sharing proposal. The battle shifted Feb. 27 when the party's head committee in Transvaal Province soundly defeated Dr. Treurnicht on his political home base. It voted 172 to 36 in support of Mr. Botha's ''leadership and his interpretation of National Party policy.''
Dr. Treurnicht and his supporters, which include another Cabinet minister, have until March 3 to reverse their votes. Treurnicht has indicated he will leave the National Party, and he will probably be removed from the Cabinet. He is expected to form a new right-wing party in opposition to the National Party.
Still, embracing the power-sharing has brought political changes that could open fresh possibilities for Mr. Botha.
''Not so long ago power sharing in all its connotations was not acceptable,'' says Prof. Gerrit Olivier of the University of Pretoria. ''Now (Mr. Botha) has legitimized the concept.''
However, just what the concept is remains to be seen. Power sharing with Indians and Coloreds has been vaguely implied in National Party constitutional proposals since 1977.
But it has never been clearly spelled out or explicitly acknowledged as power sharing. Professor Lliver points out that changes in semantics have long played an important role in political development in South Africa.
Recommendations for a new constitution and some type of power sharing are to be made this year by the President's Council, a government advisory group. Blacks, some 70 percent of the population, still are not part of the discussion.
For the National Party, the confrontation over power sharing seems destined to lead to a major split. Analysts here consider it potentially the most significant change in the National Party since Dr. Albert Hertzog broke with the National Party in 1969 over the issue of multiracial sports and formed the Herstigte (reconstituted) National Party (HNP).
Even if support is building for power sharing with Indians and Coloreds, any expectation that Mr. Botha is now poised to institute major reforms of South Africa's policy of separation of the races will most likely prove false, say analysts.
National Party scholar Willem Kleynhans of the University of South Africa contends that membership of the party is increasingly dissatisfied with Botha's reformist policies and disapproval could grow over the issue of power sharing.
''P. W. Botha cannot now surge ahead with reform. He must be even more careful,'' Professor Olivier says.
Botha will have to be cautious in assessing the depth of the split and the support Treurnicht is able to muster if he leaves the National Party, he says. However, it is also clear, says Olivier, that the prime minister has in many respects emerged from the confrontation stronger than before it.