Noun

1. • 1840, Thomas Fuller, The History of the Holy War‎

     But Baiothnoi, chief captain of the Tartarian army (for they were not admitted to speak with the great cham himself), cried quits with this friar, outvying him with the greatness and divinity of their cham; and send back by them a blunt letter...

2. An autocrat or dominant critic, especially Samuel Johnson.
   • 1997: "Sitting at a table, drinking Ale, observing the Mist thro’ the Window-Panes, Mason forty-five, the Cham sixty-four." — Thomas Pynchon, Mason & Dixon
   • 2007: The Tonsons [...] would publish Johnson's Shakespeare only by subscription, obliging the Great Cham to sell copies well ahead of publication — Michael Dobson, ‘For his Nose was as sharpe as a Pen’, London Review of Books 29:9, p. 3