Quack: A boastful pretender to arts which he does not understand. A vain boastful pretender to physick; An artful, tricking practitioner in physick.
Samuel Johnson (1839). “Dictionary of the English Language ...”
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Quack: A boastful pretender to arts which he does not understand. A vain boastful pretender to physick; An artful, tricking practitioner in physick.