An inspection or exploration of an area, especially one made to gather military information.
An exploratory survey or examination, as in seeking out information about enemy positions or installations, or as in making a preliminary geologic or engineering survey.
Reconnaissance is preliminary research or a preliminary survey such as checking out the lay-of-the-land before taking a military action.
An example of reconnaissance is when the military has a mission to go to an area and survey the enemy positions.
Origin of reconnaissance
French from Old French reconoissance recognition from reconoistre reconoiss- to recognize recognize