A boy kept to be whipped when a prince deserved chastisement.
Mungo Murray stood for Charles I., Barnaby Fitzpatrick for Edward VI.
Church History, ii. 342.) D'Ossat and Du
Perron, afterwards cardinals, were whipped by Clement VIII. for Henri
IV. of France. Also called a whip-boy.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894