turnback

turn +‎ back, from the verb phrase.

turnback (countable and uncountable, plural turnbacks)

1. (attributive) Part of a garment that is turned back.
2. The act of turning back a boat containing immigrants.
   • 2015 July 20, Paul Farrell, “Details about asylum seeker turnbacks to remain secret, commissioner rules”, in The Guardian‎:

     The information commissioner, Professor John McMillan, ruled that requests for watch officer logs and authorisations for turnbacks were exempt from release because they could have a “substantial adverse effect” on the Australian Customs and Border Protection Service (ACBPS).

3. The strap from the hames to the hip-strap, on a horse.
4. A place, e.g. on a railway, where vehicles can reverse direction, i.e. turn back.
   • 2023 June 14, David Clough, “Tram-trains are making tracks...”, in RAIL, number 985, page 54:

     Removal of one set of train turnbacks also makes more efficient use of infrastructure and reduces peak loads at interchange stations.

• “turnback”, in Collins English Dictionary.