noun
exemption from service; release from duty
Refers to being released from an obligation such as military service, prison, or public office. Often used in legal or administrative contexts.
彼は病気のため兵役を免役された。
He was exempted from military service due to illness.
免役の申請には医師の診断書が必要だ。
A doctor's certificate is required to apply for exemption from service.
Compound of 免 (exemption, dismissal) and 役 (service, duty). The exact historical derivation is uncertain, but the combination directly conveys 'release from service'.