[f. QUACK v.1 + -ING2.] That acts or practises as a quack.
1628. Venner, Baths of Bathe (1650), 357. To … reject the counsell of any quacking Physician.
1722. De Foe, Plague (1754), 39. These quacking sort of Fellows rais’d great Gains out of the miserable People.
1843. Le Fevre, Life Trav. Phys., II. I. xiv. 31. A more quacking race [Jews] of people does not exist, and they are always swallowing some kind of medicine.
