Cases of word usage

1) one complete journey round a track or race-course; the front part of a person from the waist to the knees, when sitting (lap)

2) a deep line or track (as if) made by wheels in soft ground; a way of doing something, behaving, living etc that has become (too) established (rut)

3) (a particular) smell, especially of something pleasant; perfume; a smell left by (the track of) an animal (scent)

4) to send (a train etc) from one track to another; to send (a person etc) to a different (usually worse) position (shunt)

5) a mark or series of marks left by a person or thing that has passed; a track or smell left by an animal or person; a path through rough country; (to cause something) to be pulled behind (through the air or over a surface) (trail)