DICT.TW Dictionary Taiwan

 Quack v. i. [imp. & p. p. Qvacked p. pr. & vb. n. Quacking.]
 1. To utter a sound like the cry of a duck.
 2. To make vain and loud pretensions; to boast. “ To quack of universal cures.”
 3. To act the part of a quack, or pretender.