It is used in expressions such as "what the dickens," "where the dickens," "the dickens you are!," and "the dickens you say!"
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Meaning: A lot; as in 'hurts like the dickens' or 'run like the dickens!'
Origin: Nothing to do with Charles Dickens. Dickens is a euphemism for the word devil, possibly via devilkins. Shakespeare used it in 'the Merry Wives of Windsor: 'I cannot tell what the dickens his name is my husband had him of.'