fortune in battle; luck in war; fate as a warrior
Refers to a warrior's luck or destiny in combat. Often used in set phrases like 武運を祈る (praying for success in battle).
They prayed for the soldiers' fortune in battle as they departed.
彼は武運つたなく、初陣で討ち死にした。
His luck in war was poor, and he died in his first battle.