I thought that the World’s Greatest Infectious Disease Quack already fixed HIV/AIDS.
“Quack, in the sense of a medical impostor, is a shortening of the old Dutch quacksalver (spelled kwakzalver in the modern Dutch), which originally meant a person who cures with home remedies, and then came to mean one using false cures or knowledge.
The etymological trail gets muddy if you go any further back than that, and quacksalver has been traced variously to kwakken (to fling or throw down) + zalver (person who cures with ointments), quacsalven (a term for home remedies, from the 1300s), and quaken (to quack or croak) + salf (salve). Taken figuratively, the kwakken and quaken origins imply someone peddling and boasting about their medical wares, legitimate or not—a little broader, but not too far off from the modern usage.
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