Quack

·vi To utter a sound like the cry of a duck.

II. Quack ·vi To act the part of a quack, or pretender.

III. Quack ·vi To make vain and loud pretensions; to Boast.

IV. Quack ·noun A boastful pretender to medical skill; an empiric; an ignorant practitioner.

V. Quack ·noun The cry of the duck, or a sound in imitation of it; a hoarse, quacking noise.

VI. Quack ·noun Hence, one who boastfully pretends to skill or knowledge of any kind not possessed; a charlatan.

VII. Quack ·adj Pertaining to or characterized by, boasting and pretension; used by quacks; pretending to cure diseases; as, a quack medicine; a quack doctor.