Sentence:  That 's why the FDA , the American Medical Association ( AMA ) , and the National Better Business Bureau ( BBB ) have estimated the toll of mechanical quackery to be a substantial portion of the $ 610 million or so paid to medical <WSD>charlatans</WSD> annually . 
Meaning of the word marked with <WSD> tags:  a flamboyant deceiver; one who attracts customers with tricks or jokes