I give another reference in addition to the one suggested by Barbara.
Therefore, it should be pretty correct.

fan of sidings

A large marshalling yard is generally divided into three fans of sidings. The reception sidings receive the feeder trains and connection trains from other marshalling yards. The trains are split up and then formed on the set of sorting sidings separated by the hump(s). New connection or terminal pick-up goods trains are then directed towards the departure sidings after the various safety checks have been performed (such as brake tests). There may also be a relay yard, adjacent to the train splitting sidings on which full train loads in transit may stop (to change machine or driver, for example).