overwatch

over- +‎ watch

overwatch (third-person singular simple present overwatches, present participle overwatching, simple past and past participle overwatched)

1. (transitive) To watch over.
2. (transitive) To watch excessively.
3. (transitive, obsolete) To overcome with long lack of rest.

overwatch (uncountable)

1. (military) The supervision of one unit or vehicle by another while the supervised unit is firing or moving.
   • 2007 September 11, Michael R. Gordon, “Petraeus Sees Bigger Role in Protecting Iraqi Civilians”, in New York Times‎:

     At a further and undefined point in the future, the American force would shrink to about seven and later five brigades — all involved in overwatch missions.

• watch over