short-timer

plural short-timers

1. UShistoricalslanggovernmentA soldier during the Vietnam War who had less than two months to serve.

   Almost every Marine in Viet Nam carries a short-timer’s calendar of his tour of duty—the usual 365 days—plus a bonus of 20 days for being a Marine.

   1979, Gustav Hasford, The Short-Timers, New York: Bantam Books, published 1980, →ISBN, page 45

2. governmentA person who would not be required to do a difficult or dangerous task.
3. colloquialAn employee who has given notice of their intent to leave.
4. colloquialThe customer of a prostitute.