Filed from 5 published puzzles

COVERT

Set to 5 different clues across 5 published puzzles, most often “Hidden” — The New York Times, Sunday, 4 October 2009.

6 letters

Every clue on record, most used first

Hiddenonce
The New York Times — Sunday, 4 October 2009
Hidden from viewonce
The New York Times — Monday, 22 September 2008
Not apparentonce
The New York Times — Wednesday, 8 February 2006
Like C.I.A. operationsonce
The New York Times — Monday, 5 May 2003
Hugger-muggeronce
The New York Times — Sunday, 1 January 1995

Other answers to these clues

BURIED6 letters
CACHED6 letters
ENCASED7 letters
INNER5 letters
LATENT6 letters
PERDU5 letters
SHADED6 letters
SLY3 letters
ULTERIOR8 letters
UNSEEN6 letters
VEILED6 letters