lifer

Etymology

life + -er

noun

1. A prisoner sentenced to life in prison.
2. A prisoner sentenced to transportation for life.
3. A person with a singular career path, especially in the military.
   "[…]The Top's not a lifer; he's a career Marine. Lifers are a breed. A lifer is anybody who abuses authority he doesn't deserve to have. There are plenty of civilian lifers." 1979, Gustav Hasford, The Short-Timers, New York: Bantam Books, published 1980, page 63
   LRRP planned to become “career” Army, i.e., a lifer, you kept that quiet. Basic LRRP theology said the Army sucked and that philosophy kept one from going crazy because, at the bottom, nothing about the war seemed to make sense anyway. The LRRP's considered a lifer a loser. Being a lifer implied one had no other options available. Every LRRP had his own stories about back home: about family, friends, lovers, opportunities, dreams and a future. These were mostly fantasy, but […] 2002, Paul Newman, Nine From The Ninth, iUniverse, page 17
   In the early years of EMS, the term lifer was an entitlement pinned to anyone who had worked the road for ten years or longer with no real plans of seeking a replacement trade. It was a term that was generally delivered in a respectful and lighthearted teasing manner by someone who by all definitions could have easily been described as a lifer himself—with the exception of one drawback. So far, the crews didn't know anyone who had worked in the field for ten years, much less longer […] 2005, J. M. Coutts, As the Beacon Turns, Trafford Publishing, page 392
   He was a baseball lifer, a seamhead through and through, who just absolutely liked nothing better than sitting down and talking baseball. 2018, Adrian Dater, 100 Things Rockies Fans Should Know & Do Before They Die
4. (birdwatching) A bird species seen for the first time by a birder who is keeping a list of all the species he or she has ever seen.
   I saw six species of honeyeaters new to me and went home with 16 lifers and some bad sandfly bites. 2013, Sue Taylor, Best 100 Birdwatching Sites in Australia