It might origiante from the word "quacksalver." A quackslaver was a sixteenth century word meaning a peddler who sold questionable medicine in the streets, often going from town to town. They often said their ointment, cream, vitman, or whatever they were selling could cure anything. These people pretending to have a cure came to represent a modern-day Doctor Who sold a treatment that wasn't proven to work. In searching medical treatment, it would be best to avoid this kind of doctor. These "quacksalvers" were also known as "Snake Oil Salesmen". Which is decribed as a person or organization that gains monetary benefit for the false information, service, and/or products, promised to provide a so called cure or service to the ailing (sick) and in need of healing consumer.
The term "quack" comes from the Dutch word "quacksalver," which referred to someone who boasted about their medical skills with fraudulent intent. Over time, it evolved to describe unqualified or fraudulent medical practitioners who peddled ineffective treatments.
the duck made a 'quack' noise. i went to the quack (doctor).
A duck quack
The word quack is a verb. The past tense is quacked.
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The past tense is quacked.
An example of a quack doctor is the faith healer.
a quack.
The doctor is Dr Quack!
quack (as in quack doctor) is 'un charlatan' in French. To quack (for a duck) is translated by the verbs 'cancaner' or 'craquetter'.
the duck made a 'quack' noise. i went to the quack (doctor).
quack
quack
A bad doctor can be called a quack.
Did it quack like a duck? That doctor is a quack. One "Quack!" from the duck was all it took to startle the curious puppy.
quack
Quack: the harsh, throaty cry of a duck or any similar sound.Fraud: deceit, trickery, sharp practice, or breach of confidence,perpetrated for profit or to gain some unfair or dishonest advantage.
A fake doctor is sometimes called a quack.