Bottleneck and Rubber-necking

Bottleneck noun - A crowded mass (as of cars) that impedes or blocks movement.

Rubber-necking and bottleneck are semantically related In some cases you can use "Rubber-necking" instead a noun "Bottleneck".

Rubber-necking noun - Going about to look at places of interest.

Bottleneck and rubber-necking are semantically related in blockage topic. You can use "Bottleneck" instead a noun phrase "Rubber-necking".