For viewers who may think that "cloture" is a fancy-dress coat and that "president pro tempore" is a chief of state from Latin America, the Senate Republican Policy Committee has produced a beginner's guide to the Senate in preparation for its television debut on June 2.

To explain the strange folkways of what has been called "the world's greatest deliberative body," the committee has published a 20-page "Glossary of Senate Terms -- a Guide for TV."

It has a few quirky items of historical interest, including the names of senators who became president (James Monroe was first, Richard M. Nixon was last) and that William B. Allison, not otherwise identified, held the record for tenure as a Senate committee chairman (25 years, ending in 1893).

It tells that Rebecca Latimer Felton of Georgia served the shortest term -- a day -- after being appointed before the winner of a special election was seated, and that Carl Hayden served the longest (he began representing Arizona in 1912, when it became a state, and retired 57 years later).

The pamphlet begins with this observation by Sen. William L. Armstrong (R-Colo.), chairman of the policy committee: "The Founding Fathers envisioned an upper chamber of thoughtful and experienced legislators lending a cool and detached perspective to the sometimes turbulent national policy debate. Well, sometimes it is and sometimes it isn't."

To get a copy, a viewer can write Armstrong at the Republican Policy Committee, U.S. Senate, Washington, D.C. 20510. Extension's Extension . . .

Agriculture Department officials have decided to give Edith P. Thomas two more weeks to respond to their plan to fire her from a $44,000-per-year job as an Extension Service nutritionist.

Thomas, whose GM-14 made her the highest ranking black woman in the 16,000-employe Extension Service, was told Tuesday that she was fired as of the close of business.

USDA personnel officials agreed on a 14-day extension after Thomas and her attorney complained that she had been given inadequate notice of the pending decision to release her.

USDA spokesmen denied that the firing was related to a news conference last week in which Thomas charged that the Extension Service was denying nutrition assistance to low-income minority families because of racial bias. The spokesmen said the dismissal was related to charges of misconduct, but declined to offer details. Sic Transit Gloria . . .

Senate Budget Committee Chairman Pete V. Domenici (R-N.M.) and ranking minority member Lawton Chiles (D-Fla.), delayed by a budget conference in a House office building, jumped into a Capitol Police car late Tuesday to be whisked across Capitol Plaza to make a roll-call vote on the Senate floor. But, to the embarrassment of the police officer, his vehicle stalled after making a U-turn between the Cannon and Longworth buildings in full view of a giggling gaggle of reporters who had been covering the budget conference.

Blame budget cuts under the Gramm-Rudman-Hollings law, said Chiles; the car "ran out of gas."