The Fat Lady sang in Hebrew last night and Israel loved it.

Three months to the day after winning the National Basketball Association championship in Seattle, the Washington Bullets fell victim to the ostensibly amateur Tel Aviv Maccabis, 98-97, before a wildly cheering crowd of 10,000 and a television audience estimated at more than a million people.

The almost disbelieving crowd at the new Yad Eliahu Sports Palace here mobbed the parking lot later to salute the young and lean Maccabis, who outran the visibly weary and out-of-shape Bullets all night.

Coaches and players on both teams agreed that it might have been a different story had the game been played a month or so from now, after the Bullet training camp. But Coach Dick Motta and team captain Wes Unseld agreed that the Maccabi team played "pretty doggone good" and deserved to win.

The Bullets appeared confused and frustrated by the Maccabi's zone defense, permissible under European basketball rules but not legal in the NBA.

"Some of our players haven't played the zone in 10 years, and they zoned the whole game," Motta said.

"When you come to a foreign place and play under foreign rules, you don't know what's going to happen. Considering it was the first time we played together, we played pretty good. But they played pretty good too, and they were in better shape," Motta added.

Kevin Grevey, with 31 points, and Mitch Kupchak, with 21, were the high scorers for the Bullets. Six-foot-11 center Aucie Perry, an American Basketball Association veteran who joined the Maccabis three years ago and converted to Judeaism and last month, dominated the game on defense with 10 rebounds. Mickey Berkowitz, an Israeli, led the Maccabis with 26 points. Perry had 17 and Lou Silver 16.

The Maccabis led most of the game - shortened to two 20-minute halves under European rules by 10 points, and at halftime had a 9-point edge.

As the Bullets pulled closer in the final minutes, the Israeli fans chanted "Miccabis, Maccabis," urging Israel's most popular team to do what most people here assumed was impossible.

While the Maccabis were consistently fast breaking and intercepting Bullet passes, the obviously rusty and weary Washingtonians slowed down and missed more and more outside shots.

Grevey, later visiting the Maccabi locker room, told the Israeli team, "It was a good game. You guys deserved to win. The zone neutralized us, sure, but you cannot win against a good basketball team when you aren't shooting."

The Bullets did not take the loss as a bad omen. "I came to Israel on vacation to enjoy myself. The game really was not what this trip was all about," said Bullet captin Wes Unseld. "We're having a great time in Israel and that's why we came," he added.

Perry agreed, saying that the Bullets did not need a win here but that the Maccabis had something to prove.

"I knew we were going to win. It's too early in the season for them. Rookie camp doesn't even start for a week and a half and I knew the zone defense would put them in mess. A month from now it would be a different story," said Perry.

The Maccabis, who in 1977 won the European Cup over a top-ranked Italian team in Belgrade, started practice a month ago for a season that will begin in 10 days. Apart from a 25-minute workout two days ago and a brief drill yesterday, the Bullets haven't been on the court together since they defeated Seattle in game seven of the NBA championship series June 7.

ALthough somebody forgot to bring towels for the Bullet locker room and the team had to leave for its hotel without the benefit of showers, the players seemed in good spirits and looking forward to more touring in Israel. The team has seen Jerusalem, and today will visit the Galilee, Tiberias and a nearby kibbutz, which the players said they were eager to see.

Tomorrow they will swim in the Dead Sea, visit the ruins at Massada and sightsee more in Jerusalem. They will leave Israel Monday. Practice will begin next week.

"We came here for a vacation. The game is over and now we're going to get on with the vacation," Motta said.