CFC
Set to 4 different clues across 4 published puzzles, most often “Freon initials” — The New York Times, Saturday, 13 November 2010.
3 letters
Every clue on record, most used first
- Freon initialsonce
The New York Times — Saturday, 13 November 2010
- Ozone hazard, for shortonce
The New York Times — Saturday, 22 May 2010
- Ozone depleter, for shortonce
The New York Times — Monday, 12 June 2006
- Environmental hazard, for shortonce
The New York Times — Sunday, 4 June 2000