The term 'PART OF A TRACK' can be broken down into two crossword solutions: LANE (4 letters) and RAIL (4 letters). A LANE is a section of a track that is marked off for a specific purpose, such as a running LANE or a LANE for a particular type of vehicle. A RAIL is a metal bar that is used to form the track, providing support and guidance for vehicles. Together, these two components make up a track, which is a path or course along which something moves.