look up any word, like sex:
 
1.
Clandestine Operation: An operation sponsored or conducted by governmental departments or agencies in such a way as to assure secrecy or concealment. A clandestine operation differs from a covert operation in that emphasis is placed on concealment of the operation rather than on concealment of identity of sponsor. In special operations, an activity may be both covert and clandestine and may focus equally on operational considerations and intelligence-related activities.

Not to be confused with Covert or Overt noted below.

Covert Operation: An operation that is so planned and executed as to conceal the identity of or permit plausible denial by the sponsor. A covert operation differs from a clandestine operation in that emphasis is placed on concealment of identity of sponsor rather than on concealment of the operation.

Overt Operation: An operation conducted openly, without concealment.
I'll be in the burbs - clandestine operation. shhh
by Angela R. July 14, 2006