Hurdle race and Track event

Hurdle race noun - A footrace in which contestants must negotiate a series of hurdles.

Track event and hurdle race are semantically related. In some cases you can use "Track event" instead a noun phrase "Hurdle race".

Track event noun - A footrace performed on a track (indoor or outdoor).

Hurdle race and track event are semantically related. Sometimes you can replace phrase "Hurdle race" with "Track event", this phrases are similar.