Definition of quack :
1. A boastful pretender to medical skill; an empiric; an ignorant practitioner.
2. Hence, one who boastfully pretends to skill or knowledge of any kind not possessed; a charlatan.
3. Pertaining to or characterized by, boasting and pretension; used by quacks; pretending to cure diseases; as, a quack medicine; a quack doctor.
4. The cry of the duck, or a sound in imitation of it; a hoarse, quacking noise.
5. To act the part of a quack, or pretender.
6. To make vain and loud pretensions; to boast.
7. To utter a sound like the cry of a duck.
ululate (part of speech: verb)
crow, chatter, cackle, snort, caw, growl, bleat, gobble, mew, neigh, meow, squawk, cry, whinny, cuckoo, grunt, bellow, bay, chirp, roar, snarl, cluck, moo, warble, honk, yelp, squeal, trill, twit, call, hoot, ululate, purr, howl, bawl, bray, coo, bark
ululation (part of speech: noun)
- " I'm in the hands of a quack," began Nevil Pardoe. - "First Person Paramount", Ambrose Pratt.
- But all they said was, " Quack, quack, quack!" - "Bobby of Cloverfield Farm", Helen Fuller Orton.
- And at the present day it is not at all an uncommon occurrence for medical men to be called in to prescribe for children, to whom the strongest purgative quack medicines have been previously exhibited by parents, for the removal of symptoms which, upon investigation, are found in no way connected with or produced by worms. - "The Maternal Management of Children, in Health and Disease.", Thomas Bull, M.D..