服役 literally means 'to serve duty' — 服 (fú) conveys 'to comply with, to undertake', and 役 (yì) means 'service, duty, or conscription'. Together, 服役 specifically refers to mandatory or voluntary military service in the armed forces. It is a formal, neutral-to-serious term used in official contexts, news reports, legal documents, and personal narratives about national defense obligations.

The word implies active participation in military training or operations, not just enlistment. In China, male citizens aged 18–22 are subject to compulsory military service, though actual conscription rates vary. 服役 may also describe service by volunteers or professional soldiers, and occasionally appears metaphorically (e.g., serving in emergency response units), but its core meaning remains tied to military duty. It does not apply to civilian public service, police work, or reserve training unless explicitly part of active-duty deployment.