re ‧ con ‧ nais ‧ sance /rɪˈkɒnəs ə ns, rɪˈkɒnɪs ə ns $ rɪˈkɑː-/ BrE AmE noun [uncountable and countable]
[ Date: 1800-1900 ; Language: French ; Origin: reconnaître , from Latin recognoscere ; ⇨ ↑ recognize ]
the military activity of sending soldiers and aircraft to find out about the enemy’s forces:
reconnaissance aircraft
a reconnaissance mission
wartime roles such as observation and reconnaissance