A large all-black passerine bird in the crow family, Corvus corax.
A dark-colored South Asian swallowtail butterfly, Papilio castor
The sound made by a duck.
A fraudulent healer, especially a bombastic peddler in worthless treatments, a doctor who makes false diagnoses for monetary benefit, or an untrained or poorly trained doctor who uses fraudulent credentials to attract patients
Any similar charlatan or incompetent professional.
Any doctor.
Falsely presented as having medicinal powers.
To make a noise like a duck.
Of a queen bee: to make a high-pitched sound during certain stages of development.
To practice or commit quackery (fraudulent medicine).