self-opening

From self- +‎ opening

self-opening (not comparable)

1. (Of an object) that opens, or is designed to open automatically, or opens of its own accord.
   • 1963 January, “New in Japan: A Vista-car special”, in Modern Railways, page 44:

     Special features enable the cars to be used as mobile classrooms; equipment includes a microphone and inter-car broadcasting equipment, self-opening doors, fluorescent lights, illuminated speedometer, carton disposal units and a folding bed which normally serves as seats on either side of a table.

• “self-opening” in Lexico, Dictionary.com; Oxford University Press.