Noun
a military operation carried out cooperatively by two or more allied nations or a military operation carried out by coordination of sea, land, and air forces
Source: WordNetThis uncoordinated advance caused great difficulties in planning for the commanders of the combined operation, as they now found themselves with a convert string of indefensible positions on their southern flank. Source: Internet
The following year saw a combined operation planned by Constantius to regain control of the Rhine from the Germanic peoples who had spilt across the river onto the west bank. Source: Internet