Answer:

secret

AnswerCrossword Clue
SECRETHush-hush
SECRETUndisclosed
SECRETHidden, as eight related pieces in the grid
SECRETPrivileged info
SECRETBack-room
SECRETIt's not for everyone
SECRETWhispered item
SECRETUnder wraps
SECRETKind of agent
SECRETHidden
SECRETSkeleton, so to speak
SECRETConfidant's confidence
SECRETUnder wraps, so to speak
SECRETFor only a select few
SECRETWhispered thing
SECRETConfidence
SECRETSkeleton in the closet, e.g.
SECRET"The ... of Nimh" (1982 cartoon)
SECRETUndercover
SECRETWhispered words
SECRETNot publicly known
SECRETUnrevealed
SECRET"I've Got a ..." (game show)
SECRETWith "The," popular self-help book
SECRETLike passwords or passcodes
SECRET"The ... Garden"
SECRETConfidential manner
SECRETConfidential matter
SECRETIt may be told in anger
SECRETWord after top or trade
SECRETCryptic
SECRETSomething to keep
SECRET"I've Got a .."
SECRETClandestine
SECRETLike some ballots
SECRETSomething to whisper
SECRETConcealed
SECRETConfidential item
SECRETConfidential
SECRETSomething confidential