William Julius Wilson, the University of Chicago sociologist widely credited with reviving research into the problems of the poorest of the poor, yesterday said he may abandon the use of the word "underclass" in order to discourage analyses that blame the poor for their plight.

Wilson's 1987 magnum opus, "The Truly Disadvantaged: The Inner City, the Underclass, and Public Policy," and his 1980 book "The Declining Significance of Race," helped place the heavily black and Hispanic U.S. underclass at the center of much domestic public policy debate.

Wilson, in the presidential address at the annual meeting of the American Sociological Association, told the organization that "a spate of studies highly critical of the term 'underclass' has accompanied the increased research activity on the inner-city ghetto. The general view is that the term ought to be rejected because it has become a code word for inner-city blacks, has enabled journalists to focus on unflattering behavior in the ghetto, and has no scientific usefulness."

Wilson defended use of the word 'underclass' to describe concentrations of the very poor -- among whom problems of unemployment, crime, illegitimacy and poor education are severe -- because it "led to a more precise specification. . . concerning life in the inner-city ghetto."

But, he acknowledged, in order to "move us away from the controversy . . . I will substitute the term 'ghetto poor' for the term 'underclass.' " In an interview after his speech, he said he had not decided whether to give the word up permanently.

Sheldon Danziger, a specialist in the study of poverty at the University of Michigan, said he was surprised and concerned at Wilson's action.

Danziger argued that the concept of the underclass "has served as a valuable bridge between conservatives and liberals." He suggested that it forced conservatives to reevaluate their view that the roughly 30 million people who are poor share the severe problems of the underclass, when in fact most do not and the underclass is a much smaller population of about 2 million.

Conversely, the severity of the problems of the underclass has forced liberals to reevaluate the usefulness of traditional policies, including expanded welfare benefits and promotion of full employment, Danziger said.

Wilson also used his speech to defend and elaborate on themes in "The Truly Disadvantaged."

There are three central elements to Wilson's argument:

A major factor in the sharp increase in black urban unemployment has been the decline in low-skill but relatively high-paying manufacturing jobs in major northeastern and midwestern cities. "The bottom fell out in urban and industrial demand for poorly educated blacks," Wilson said, citing the work of political scientist John Kasarda.

Three-quarters of the increase in ghetto poverty, or the underclass, occurred in 10 cities, half in New York and Chicago alone.

Black and Hispanic poverty has become increasingly concentrated in urban neighborhoods as middle class members moved to the suburbs. "{I} argue that the central predicament of inner-city ghetto residents is joblessness reinforced by growing social isolation in impoverished neighborhoods," Wilson said yesterday.

Joblessness and isolation combined to accelerate and intensify weak labor force attachment, a low level of "psychological self-efficacy" and decay of the family structure. These are "what I have called 'concentration effects' -- that is, the effects of living in a neighborhood that is overwhelmingly impoverished," Wilson said.

Wilson's work has been a major force in expanding the examination of poverty, although a number of his arguments have been questioned.

Isabel Sawhill of the Urban Institute praised Wilson for "changing the debate by allowing serious social problems in the ghetto to once more be addressed by social scientists who don't have a political agenda."

But she contended that black unemployment has risen not only from a jobs mismatch but also from substantial "skills mismatch": "It's not only to do with the subway system between Harlem and midtown Manhattan but it also has to do with education in Harlem and the jobs in Manhattan. I think it's more serious -- a skills mismatch rather than a spatial mismatch."

After his speech Wilson was given the 1990 Dubois-Johnson-Frazier Award for "research excellence in the tradition of these black academics."