Brian Aherne, 83, who epitomized the debonair, self-assured British gentlemen in more than three dozen films while simultaneously establishing himself as a viable stage presence, died Feb. 10 at a hospital in Venice, Fla. He had a heart ailment.

Retired from the stage and screen for nearly 20 years, Mr. Aherne in his prime played opposite some of the most glamorous actresses of the century: Marlene Dietrich, Katharine Cornell, Helen Hayes, Katharine Hepburn, Madeleine Carroll and Bette Davis. In most of those appearances he was the impeccably mannered and meticulously groomed consort to their more tempestuous characters.

Born in Britain, Mr. Aherne studied architecture, but he turned to the stage in 1923. He appeared in films and toured Australia with a stage company before coming to this country.

He made his Broadway debut in 1931, portraying Robert Browning opposite Cornell in "The Barretts of Wimpole Street." A New York Times critic hailed his performance as "all strength, kindness and sincerity."

He was lured from the touring company of "Barretts" to appear on screen opposite Dietrich in "Song of Songs" in 1933, launching a film career that was to end in 1967 in "Rosie" with Rosalind Russell. In between were "Beloved Enemy," "Juarez," "My Son, My Son," "Skylark," "My Sister Eileen," "Forever and a Day" and "The Swan," among others.

In later years, Mr. Aherne made two distinctive stage appearances -- as George Bernard Shaw opposite Cornell in "Dear Liar" and as Henry Higgins in the touring company of "My Fair Lady."

In 1939, Mr. Aherne married actress Joan Fontaine but they were divorced in 1944. Two years later he wed Eleanor Labrout, who survives him.