noun
defence forces; defence corps
Refers to a military organization responsible for national defence; often used in proper names like 自衛隊 (Japan Self-Defence Forces) or 国防軍.
その国は強力な防衛軍を持っている。
That country has a powerful defence force.
防衛軍の演習が来月行われる。
The defence forces' exercise will be held next month.
国防軍 is another term for national defence forces, often used in historical or political contexts, whereas 防衛軍 is a broader and more neutral term.
Compound of 防衛 (defence) + 軍 (army, forces). The term is a straightforward Sino-Japanese compound.