KEYHOLE

Set to 4 different clues across 4 published puzzles, most often “Listening post?” — The New York Times, Saturday, 9 September 2006.

7 letters

Every clue on record, most used first

Listening post?once
The New York Times — Saturday, 9 September 2006
Peeper's placeonce
The New York Times — Wednesday, 8 October 2003
Area at each end of a basketball courtonce
The New York Times — Saturday, 18 May 1996
Voyeur's vantageonce
The New York Times — Saturday, 2 September 1995