A stool or chair in which miscreants were confined and subject to ducking and public shame. Perhaps given the source of the word cuck, it was not vegetables which were thrown at victims; it was also referred to as cathedra stercoris = the chair of excrement. It is found in Chester, in the 11c and later, e.g. for the brewers of bad ale: the monetary penalty was 4s, as specified in the city's entry in *DB - more than a brewer could afford. [< OldEngl. kukr = excrement] -
Cf. Pillory
Dictionary of Medieval Terms and Phrases. Christopher Coredon with Ann Williams.