adj. Describes a crossword puzzle fan or constructor who has passed away.
1997
You know, I discovered another piece of slang in the crossword puzzle. I just found myself drawn to this. "Six down" is something I had never heard before. It's a term of endearment for great crossword puzzle constructors who have passed away. So you write Eugene Moleska (ph) became six down on August 3, 1993.
1986 (earliest)
Re, H. G. Knapp's letter, Are crossword puzzles for Americans only? (June 10). I agree wholeheartedly with him, and if he wants to contact me and bring a shovel we can go down to the States and get the guy who makes these crosswords up for The Star and bury him 6 down and 3 across!