Loop-line and Stirrup

Loop-line noun - A railway branch line that branches from the trunk line and then rejoins it later on.

Stirrup and loop-line are semantically related. In some cases you can use "Stirrup" instead a noun phrase "Loop-line".

Stirrup noun - Support consisting of metal loops into which rider's feet go.

Loop-line and stirrup are semantically related. Sometimes you can replace phrase "Loop-line" with "Stirrup", this terms are similar.