United States Government Glossary of Interagency and Associated Terms/active military, naval, or air service

by Federal Government of the United States

active military, naval, or air service - (A) active duty; (B) any period of active duty for training during which the individual concerned was disabled or died from a disease or injury incurred or aggravated in line of duty; and (C) any period of inactive duty training during which the individual concerned was disabled or died (i) from an injury incurred or aggravated in line of duty; or (ii) from an acute myocardial infarction, a cardiac arrest, or a cerebrovascular accident occurring during such training.

(SOURCE - DVA, US Code 38, §101.)