Having completed one's term of enlistment or service.
The Century Dictionary (Public Domain)
Use "time-expired" in a sentence
"He was a time-expired UN remote-control peacekeeper, out of the military at sixteen; who had taken the free Lottery option as part of his severance pay."
"On the deck sailors and time-expired soldiers were lying asleep side by side; there were so many of them it was difficult to pass."
"They was still discharging time-expired men long after I got my papers."