An intelligence operation so planned as to permit plausible denial by the sponsor(noun)
WordNet. Princeton University. 2010.
Use "covert operation" in a sentence
"The thundering navy SeaHawk chopper had been scrambled under a covert operation status out of Thule Air Force Base in northern Greenland."
"At that meeting on Pearl Harbor Day, 1985, when we considered continuing and possibly even expanding the covert operation begun the previous summer, they made their opposition clear to me forcefully."