A casual phrase can be a diplomat's undoing. Just ask William Schaufele. He is the American ambassador to Greece who was confirmed by the Senate last summer but has yet to begin his job. The reason: he said two words that enraged Greek politicians and the press.

For the past several months Schaufele (pronounced "Shau-Flay") has been holding down a desk at the State Department while Secretary of State Cyrus Vances tries to persuade Greece to accept the career foreign service officer in Athens. A meeting late last September between Vance and the Greek foreign minister in New York was inconclusive, so Schaufele continues to work in the office of Greek affairs at Foggy Bottom, an impatient ambassador without a country.

"Waiting is difficult for someone who has been active," admits Schaufele, former assistant secretary of state for African affairs and ambassador to Upper Volta between 1969 and 1971.

His wait began in July after he said at his confirmation hearings: "The Aegean, essentially, is a bilateral dispute between Greece and Turkey which in part is due to the unusual, I must admit, arrangements that have been made about geography in the past in which you have Greece owning territory very close to the Turkish coast as a result of past international agreements."

The words "unusual arrangements" enraged Greeks who felt Schaufele disapproved of Greek control of islands such as Lesbos and Chios. Politicians from both the Greek socialist party and the United Democratic Left attacked Schaufele as an advocate of Turkish views. The State Department issued an edited transcript of the hearing which put the quotation more diplomatically: "The problem (of the Aegean) is due in part to an unusual arrangement of geography. Greece owns territory very close to the Turkish coast. This ownership is based on long-standing international agreements."

If didn't soften Greece's displeasure, and the brouhaha threw a wrench in Schaufele's life. His wife had quit her job and the family was preparing to rent their Bethesda home when everything came to a halt.

"I've been in this business twenty-seven years," Schaufele says with a tight laugh, "and didn't get too much leave anyway." Now he has plenty of time for vacation while he plays a waiting game. But there is one topic of conversation he refuses to discuss with anyone: Greek politics.