RND

Set to 4 different clues across 4 published puzzles, most often “Circular: Abbr.” — The New York Times, Thursday, 10 May 2001.

3 letters

Every clue on record, most used first

Circular: Abbr.once
The New York Times — Thursday, 10 May 2001
Not sq.once
The New York Times — Saturday, 8 May 1999
Three min. in the ringonce
The New York Times — Sunday, 10 May 1998
Three minutes, in boxing: Abbr.once
The New York Times — Thursday, 19 December 1996