QUACK Meaning of QUACK in English v. & n.n. the harsh sound made by ducks. v.intr. 1 utter this sound. 2 colloq. talk loudly and foolishly. [ imit.: cf. Du. kwakken, G quacken croak, quack ] Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012