The supervision of one unit or vehicle by another while the supervised unit is firing or moving.(noun)
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Use "overwatch" in a sentence
"By next fall the Marines plan to be in what they call an "overwatch" role."
"= SPEED!., transit open terrain, especially at night, day travel and leap frogging or overwatch is to slow and depends on the crew mack up. unless contact is expected and unavoidable, then leap/overwatch is noty a big issue."
"A little more than a decade on, his most common mission is what is called an "overwatch," scanning the ground via infrared sensors and radioing what he sees to troops below."