“退伍” v. be discharged from active military service; leave the army（Source: 《新世纪汉英大词典》）
“军人” n. soldier; serviceman; army man（Source: 《新世纪汉英大词典》）
“退伍军人” n. retired soldier; veteran（Source: 《新世纪汉英大词典》）

新闻例句

美国海军海洋系统司令部枪击案死难者人数已经上升至13人，包括已被击毙的枪手、海军退伍军人亚伦•亚历克西斯。 （Source: 中国新闻网）

The death toll of the Washington Yard shooting has risen to 13, including the deceased gunman, former US Navy reservist Aaron Alexis.