track magnet

English

Noun

track magnet (plural track magnets)

1. (rail transport) A magnet incorporated in railway track for various purposes.
   • 1960 December, “Talking of Trains: Recording electric operation”, in Trains Illustrated, page 707:

     Train positions and speeds were established by a track magnet at each milepost, which produced a suitable mark on the punched recording tape whenever a train passed.