grand master 
noun
1 (usually grandmaster) A chess player of the highest class, especially one who has won an international tournament.Her mother Joan, by the way, is the sister of chess grandmaster Bobby Fischer....
- Preferably, it has been written by a grandmaster or international master who actually plays the line in question.
- He hopes Russian grandmaster and former world chess champion Gary Kasparov will give guest lectures.
2 (Grand Master) The head of an order of chivalry or of Freemasons.The famous King Henry the Navigator was a known Grand Master of the Order....
- The house dates back two hundred years and was built by the local Grand Master of the Freemasons.
- He then orders the Grand Master to leave with his Templars.