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definitions

quack

2
[kwak]
||

noun

a fraudulent or ignorant pretender to medical skill.
a person who pretends, professionally or publicly, to skill, knowledge, or qualifications he or she does not possess; a charlatan.

adjective

verb (used with object)

to treat in the manner of a quack.
to advertise or sell with fraudulent claims.

Origin of quack

2
First recorded in 1620–30; short for quacksalver
Related formsquack·ish, adjectivequack·ish·ly, adverbquack·ish·ness, noun

Synonyms for quack

2. mountebank, phony.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for quacker

simulated, bum, pseudo, phony, pretended, fake, sham, dissembling, mountebank, faker, sharp, whip, counterfeit, actor, cheat, counterfeiter, humbug, pretender, fraud, impostor

Examples from the Web for quacker

Historical Examples of quacker

  • And all the time she didn't pay the least attention to Quacker the Duck.

    Old Granny Fox

    Thornton W. Burgess

  • Now it just happened that at that very minute Quacker chanced to look that way.

    Old Granny Fox

    Thornton W. Burgess

  • Quacker drummed his prettiest—“Quack-quack, quack-quack, quack-quack!”

  • As he crept along, Reddy wondered if it could be that for once Quacker had come ashore.

    Old Granny Fox

    Thornton W. Burgess

  • Why, she walked right out on the little beach just below Reddy and in plain sight of Quacker!

    Old Granny Fox

    Thornton W. Burgess

British Dictionary definitions for quacker

quack

1

verb (intr)

(of a duck) to utter a harsh guttural sound
to make a noise like a duck

noun

the harsh guttural sound made by a duck

Word Origin for quack

C17: of imitative origin; related to Dutch kwakken, German quacken

quack

2

noun

  1. an unqualified person who claims medical knowledge or other skills
  2. (as modifier)a quack doctor
British, Australian and NZ informal a doctor; physician or surgeon

verb

(intr) to act in the manner of a quack
Derived Formsquackish, adjective

Word Origin for quack

C17: short for quacksalver
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for quacker
n.

"a duck," 1846, agent noun from quack (v.).

quack

v.

"to make a duck sound," 1610s, earlier quake (1520s), variant of quelke (early 14c.), of echoic origin (cf. Middle Dutch quacken, Old Church Slavonic kvakati, Latin coaxare "to croak," Greek koax "the croaking of frogs," Hittite akuwakuwash "frog"). Middle English on the quakke (14c.) meant "hoarse, croaking." Related: Quacked; quacking.

quack

n.1

"medical charlatan," 1630s, short for quacksalver (1570s), from obsolete Dutch quacksalver (modern kwakzalver), literally "hawker of salve," from Middle Dutch quacken "to brag, boast," literally "to croak" (see quack (v.)) + salf "salve," salven "to rub with ointment" (see salve (v.)). As an adjective from 1650s. The oldest attested form of the word in this sense in English is as a verb, "to play the quack" (1620s). The Dutch word also is the source of German Quacksalber, Danish kvaksalver, Swedish kvacksalvare.

quack

n.2

duck sound, 1839, from quack (v.).

Online Etymology Dictionary, © 2010 Douglas Harper
quacker in Medicine

quack

[kwăk]

n.

An untrained person who pretends to be a physician and dispenses medical advice and treatment.
A charlatan.
Related formsquack′er•y n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.