non-runner

noun3

1. •
   One who does not take part in the physical activity of running.
2. •
   A racehorse that is withdrawn before the start of a race.

   • There were two non-runners in the three o'clock at Puddletown.
3. •
   A vehicle that cannot move under its own power, owing to mechanical defect or failure.

   • The Merc on the forecourt is a non-runner.