Funny town, Washington. Omit the after-dinner toast and tongues start to wag. On Embassy Row, if omitting the toast is not tantamount to war, the next worst possibility could be a diplomatic slight.

Take last night, for instance, at the black-tie dinner for Jordan's King Hussein and Queen Noor given by Jordanian Ambassador and Mrs. Sharf. No toasts -- by anyone -- after a two-hour feast for 200 top-level guests, including the chief justice, most of the Arab states' ambassasors, a dozen or more key members of Congress, top Pentagon and State Department brass and some of the best-known names in American journalism.

People were downright shocked at some tables in Anderson House, the elegant Massachusetts Avenue mansion belonging to descendants of the exclusive Revolutionary War veterans group called the Society of the Cincinnati, which regularly rents it out to visiting Middle Eastern potentates and kings.

Some guests were sure that Hussein's failure to raise a goblet signaled not only bad news for the Egyptain-Israeli peace front but maybe even a total breakdown in Jimmy Carter's attempts to bring Hussein into the peace-making process. When someone asked Harold Saudners, assistant secretary of state for Near Eastern and South Asian Affairs, if that explained the absence of toasts he could hardly contain his dismay.

"Oh, no," Saunders told June Bingham, wife of the New York congressman, "that's why we get into so much trouble when things happen. People have to invent reasons."

At the table where Soviet Ambassador Anatoliy Dobrynin, Moroccan Ambassador Ali-Bengelloun and Lorrine Percy sat, it wasn't to much inventing reasons as filling the void. "We toasted everybody -- the king's new baby, the queen, all the beautiful women in the room. It was the best table in the room," said the wife of Illnois Republican Charles Percy.

House Majority Leader Jim Wright of Texas Decided there probably was "greater eloquence in silence" when all was and done since "so often in diplomatic language we will tiptoe up to the brink of a subject, then back off in fear of falling."

Arab League Ambassador Clovis Maksoud probably offered the most logical explanation: Since the dinner was given by Jordan's ambassador for the king, for either one to offer a toast would have amounted to them talking to each other.

The dinner was the second one in which Hussein showed off his American-born queen to the city where she was born. With his two sons by his second marriage, princes Faisal and Abdullah, Hussein and Noor (meaning "light") welcomed a high-powered guest list that included ABC-TV's Barbara Walters, Frank Reynolds and Bob Clark, Agronsky and Co.'s Martin Agronsky, Houser Foreign Affairs Committee Chairman Clement Zablocki, Gen. David Jones of the Joint Chiefs of Staff, Richard Lugar (R-Ind.) and Richard Stone (D-Fla.)

"Everybody says there's been no trouble," Sen. Charles Mathias (R-Md.) observed with wry humor, "so everybody's turned up to prove there's been no trouble."

"After all," said Rep. John Brademas (D.Ind.) crafting a turn of phrase, "kings and queens ought to be attended to. We have tensions with many countries -- they're like marriages, you know. In diplomatic as well as domestic politics, lubrication is very important -- and I'm not speaking of oil."

Hussein's return to Washington after a three-year absence was greeted with optimism by several in the crowd, including Rep. Stephen Solarz (D-N.Y.) "You know it used to be said that King Jussein would be the second Arab leader to make peace with Israel," said Solarz, member of the foreign affairs committee's subcommittee on Middle Eastern affairs. "Now that we've had the first, we're waiting for the second."

U.S. Ambassador to Jordan Nicholas A. Veliotes wasn't exactly eager to talk about it but said discussions have been held "off and on" with the Congress concerning what he called the "ongoing modernization" of Jordan's military hardware. "Tanks and other equipment would be within that context -- so it's no great surprise, you know," Veliotes said.

Among the guests were Doris Halaby, Queen Noor's mother who said her first grandson, Prince Hamzah, had the distinction of being the youngest official vistor ever to stay in Blair House, the presidential guest house.

"I know because I had to find out if they had any of the things on hand Her Majesty said she needed. They didn't," said Doris Halaby, "so I bought them."