long-running

comparative longer-running · superlative longest-running

1. Operating for a relatively extended period of time.

   The long-running play finally closed on Broadway, just short of setting a record for longest playing.

   2 more examples

   Services on SWR's neighbour Southern were badly disrupted for nearly 40 days in 2016-17 following a long-running dispute involving drivers union ASLEF and the RMT. And it's passengers - the very people the railway is there for - who are caught in the middle.

   2019 December 18, Richard Clinnick, “Railway's 2020 vision”, in Rail, page 3

   It’s one of the world’s longest-running experiments, having already gone on for 142 years. And the botanists in East Lansing hope that it will last for at least another 80.

   2021 April 21, Cara Giaimo, “One of the World’s Oldest Science Experiments Comes Up From the Dirt”, in The New York Times, archived from the original on 27 Apr 2021