Waverley Lewis Root, 79, a journalist who had written from Paris for more than 50 years and was The Washington Post correspondent there for 12 years before retiring from daily journalism in 1969, died of a pulmonary edema Oct. 30 in his home in Paris.

He was this paper's first regular correspondent from Paris, contributing articles on French politics, culture and life. He also ranged farther afield, covering events from other European capitals as well as from trouble spots in North Africa.

Returning to Paris after World War II, he became known as an expert on French foods and cooking, and was the author of several books including the definitive "Food . . . An Informal Guide."

Mr. Root was born in Providence, R.I., reared in Fall River, Mass., and attended Tufts University. He lived in Greenwich Village, where he wrote book reviews and short stories. He once told an interviewer that he wrote musical criticism for several obscure publications and thought them no worse than what was written in more solemn publications.

In 1927, he decided to visit Paris for a few weeks.

Upon arriving there, he took a job as a reporter with the old Paris edition of the Chicago Tribune, which was published from 1925 to 1934. Among his colleagues there were James Thurber, William L. Shirer and Henry Miller. Mr. Root was its news editor and wrote a weekly book page.

After the Chicago Tribune folded in Paris, he became a cable editor with the old United Press, was a reporter for Time magazine and the Danish paper Politiken, and became the French representative of the Mutual Broadcasting System. He also worked for Newsweek and the old Chicago Times.

Among the stories he covered in those early days were the Lindbergh flight in 1927, the London Naval Conference and the major events leading to World War II.

During World War II, he did a nightly news broadcast from New York City from station WINS. He also was an editor of the New York Daily Mirror and wrote books about the war.

His philosophy of reporting was not the most orthodox. He once wrote that "journalism is essentially unskilled labor," and that "a young man coming out of college trained for no particular job, and not a good enough salesman to peddle bonds, naturally gravitates into journalism."

In addition to daily journalism, Mr. Root was the coauthor of a three- volume study of the secret history of World War II, and the Paris editor of Holiday magazine.

He was a founder, along with H.V. Kaltenborn, Raymond Gram Swing and Elmer Davis, of the Association of Radio News Analysts. He had been a member of the board of governors of the Overseas Press Club.

He also appeared episodically over the years, under other names, as a character in a dozen or so novels, the best known of which is Elliott Paul's "The Last Time I Saw Paris."

Mr. Root was an authority on French foods and cooking. After more than 30 years as a news correspondent, he published "The Food of France" in 1958, which never went out of print, was never translated into French, and inspired another gastronomic classic, "Between Meals" by Mr. Root's longtime friend, A.J. Liebling.

That book was followed by several books in which Mr. Root combined gastronomic gusto with lively erudition. The crowning work was "Food," published in 1980, which Mr. Root subtitled "An Informal Guide" and which his publisher renamed "An Authoritative and Visual History and Dictionary of the Foods of the World."

"Food" took nearly 10 years of work. Selections were for a long time printed in the International Herald Tribune in Paris with a note that the complete dictionary would be published soon. The word "soon" was eventually dropped. At one point Mr. Root thought it would be a million words long, at another he reported that he was working on a 150,000-word abridgement of which 200,000 words had already been written.

He was an officer of the French Legion of Honor.

Three marriages ended in divorce.

Survivors include his wife, Colette, of Paris; a daughter, Diane Root of New York City, and two sisters, Winifred Root of Rockport, Mass., and Martha Root of Albuquerque, N.M.