In Great Britain and many of its former colonies, “judgement” is still the correct spelling, but ever since Noah Webster decreed the first E superfluous, Americans have omitted it. Many of Webster’s crotchets have faded away (each year fewer people use the spelling “theater,” for instance), but even the producers of Terminator 2: Judgment Day chose the traditional American spelling. If you write “judgement” you should also write “colour.”
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