Quackish

[kwak] /kwæk/

noun
1.
a fraudulent or ignorant pretender to medical skill.
2.
a person who pretends, professionally or publicly, to skill, knowledge, or qualifications he or she does not possess; a charlatan.
adjective
3.
being a quack:
a quack psychologist who complicates everyone’s problems.
4.
presented falsely as having curative powers:
quack medicine.
5.
of, relating to, or befitting a quack or :
quack methods.
verb (used with object)
6.
to treat in the manner of a quack.
7.
to advertise or sell with fraudulent claims.
/kwæk/
verb (intransitive)
1.
(of a duck) to utter a harsh guttural sound
2.
to make a noise like a duck
noun
3.
the harsh guttural sound made by a duck
/kwæk/
noun
1.

2.
(Brit & Austral, NZ, informal) a doctor; physician or surgeon
verb
3.
(intransitive) to act in the manner of a 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.
n.

“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.

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

quack (kwāk)
n.

quack’er·y n.

noun

An incompetent and fraudulent doctor

[1659+; a shortening of quacksalver, ”a person who boasts about the virtues of his worthless remedies”; fr Dutch and found by 1579]