The position of troops drawn up in their usual order without any determined maneuver.(noun)
The line or arrangement formed by vessels of war in an engagement.(noun)
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Use "line of battle" in a sentence
"To Hill it may have seemed a long, long time before Heth's line of battle came in sight."
"When the fleet of any nation actually beleaguers the port of its enemy, no other has a right to enter their line, any more than their line of battle in the open sea, or their lines of circumvallation, or of encampment, or of battle array on land."
"These Virginians and Georgians were in line of battle to the right of and parallel to the Plank Road and about sixty yards from it."