Like a quack (fraudulent doctor), or characteristic of quackery.
quackishly
quackishly
adv
In a quackish manner.
quackishness
quackishness
noun
The state or condition of being quackish.
quackism
quackism
noun
Behaviour of a quack; quackery.
quackisms
quackisms
noun
plural of quackism
quarterdeckish
quickens
quickens
noun
(chiefly Midlands (northern), Northern England, Northern Ireland, Scotland) Synonym of couch grass (“a species of grass, Elymus repens”); also, the underground rhizomes of this, and sometimes other grasses.