used as a euphemism for “fuck off” CANADA Said by Canadian Prime Minister Pierre Trudeau in the House of Commons, 16th February 1971.
— Maledicta, pp. 182–183, 1979: “Canadian slurs, ethnic and other”
He had been caught in the House silently mouthing a four-letter word. But outside the house he told the press he’d said “fuddle-duddle.” As one Parliament wag remarked, “The PM wants to be obscene and not heard.” — Bill Casselman, CanadianWords, pp. 146–147, 1995