President Bush yesterday vetoed the Civil Rights Act of 1990, prompting the sharpest criticism he has endured from women, unions, blacks and other minorities since taking office.

In a three-page veto message to Congress, Bush said that "despite the use of the term 'civil rights,' " the legislation "actually employs a maze of highly legalistic language to introduce the destructive force of quotas" in the workplace.

The dispute has centered largely on the defenses available in the legislation to employers sued for so-called "unintentional" discrimination. The White House has charged that the provisions in the bill were so burdensome to employers that they would create "powerful incentives" for them to "adopt hiring and promotion quotas" to avoid lawsuits, as the president said yesterday in his veto message.

Proponents of the bill contend that it essentially would have restored the law of employment discrimination that had been in force for nearly two decades, prior to six recent Supreme Court rulings that made it more difficult for minorities and women to win discrimination suits. They strongly dispute the contention that the new law would result in quotas.

Equal opportunity, Bush said, is "thwarted," not served, by quotas, and "the very commitment to justice and equality that is offered as the reason why this bill should be signed requires me to veto it."

The Senate has scheduled for today a vote on overriding Bush's veto. But White House press secretary Marlin Fitzwater as well as civil rights groups agreed they lack the two-thirds majority needed to override. The Senate vote for passage was 62 to 34; the House vote was 273 to 154.

Bush, who enjoyed a cordial relationship with civil rights leaders even in the bitter years of the Reagan administration, found himself yesterday being described as Reagan in disguise.

"The rhetoric may be gentler and kinder, but the policies of George Bush are no less dangerous and regressive than those of Ronald Reagan and Ed Meese," said Ralph Neas, executive director of the Leadership Conference on Civil Rights.

Arthur Kropp of People for the American Way accused Bush of trying to "out-Reagan Reagan." John Sturdivant, president of the American Federation of Government Employees, accused Bush of "political rhetoric designed to please Jesse Helms, David Duke and their followers in the ultra-right-wing of the Republican Party."

Sen. Edward M. Kennedy (D-Mass.) said Bush's veto demonstrates "that he is more interested in appeasing extremists in his party than in providing simple justice" for working Americans.

Business groups strongly opposed the legislation and a coalition that includes the Chamber of Commerce, the National Association of Manufacturers and several dozen smaller groups worked against it, agreeing that it would impose too complex and severe a burden on employers. The Landmark Legal Foundation, a conservative legal think tank, applauded the veto as "a tremendous act of political courage" by the president.

Clint Bolick, the foundation's director, said the civil rights leadership is "out of touch with the people it claims to represent," and he called on Congress to fashion civil rights measures directed toward "individual empowerment" such as expanded educational opportunities and more choice in education.

Bush's veto message, in fact, endorses such alternatives and calls on Congress to give parents more choice in education, to strengthen the fight against crime and drugs, and to "empower individual Americans."

His message said that the "incentives" for quotas in the bill "are created by {its} new and very technical rules of litigation, which will make it difficult for employers to defend legitimate employment practices. In many cases," the message stated, "a defense against unfounded allegations will be impossible."

The veto came after Fitzwater said supporters of the bill, who include the most senior blacks in the Bush administration, the Republican-led U.S. Civil Rights Commission, and majorities in both houses of Congress, do not understand the legislation they had asked Bush to sign.

"A lot of them don't understand the legal implications of the bill," Fitzwater said of the bill's advocates, "many of them don't know what's in the bill."

In the veto message, Bush called on Congress to support his alternative legislation, submitted Saturday night. With a few days left in this session of Congress, leaders there and White House officials acknowledged yesterday that the Bush package had no realistic chance of passage and was meant to demonstrate his desire for civil rights legislation.

Despite the dim prospects, Sen. Arlen Specter (R-Pa.) last night began circulating new language to fellow Republicans and to the White House with hopes it could be incorporated into the Bush legislation and produce the elusive compromise.

Since May, White House and Justice Department officials have spent hundreds of hours of talks with bill sponsors and civil rights lawyers trying to work out acceptable language.

In the black commmunity, the phrase "disappointment" emerged from numerous statements. Bush over the past 20 months has enjoyed approval ratings among blacks nearly as high as his approval among non-blacks, a phenomenon not seen for a Republican president since the Eisenhower administration.

Benjamin L. Hooks, executive director of the NAACP, with whom Bush often speaks on civil rights issues, called the veto "a sharp and shocking disappointment" and said he was "at a loss" to understand why the president describes the legislation as a quota bill.

Because the legislation would have extended new protection against discrimination to women, groups representing women reacted sharply yesterday as well.

"President Bush today told millions of hard-working American women struggling to support themselves and their families during frightening economic times that it is okay for their bosses to discriminate against them," Judith Lichtman, president of the Women's Legal Defense Fund, said, echoing statements of several other organizations.

One of the few new provisions in the legislation would have allowed women who were victims of intentional discrimination to recover damages as well as back pay after a jury trial. Under current law, women may be awarded back pay and get their jobs back, but damages are not allowed.

Many black Republicans, including some in the Bush administration, backed the legislation the president vetoed. In August, Bush's top black appointees, Secretary of Health and Human Services Louis W. Sullivan and Constance Newman, head of the Office of Personnel Management, traveled to Kennebunkport, Maine, when Bush was vacationing to ask that he not veto the legislation.

Their appeals, along with that of Arthur A. Fletcher, head of the Civil Rights Commission, and of William T. Coleman Jr., the former transportation secretary Bush enlisted to broker an agreement, were reiterated in recent weeks, administration officials said.

Thomas Homburger of the Anti-Defamation League, noting the strong opposition Jews historically have had to numerical preferences and quotas of any type, said, "this act is simply not a quota bill."