There are multiple definitions:

1. double-J [stent](English)

   • associated with higher risk of infection (UTI)
   • CA-UTI
   • Urology, Microbiology, Risk factor
   • https://doi.org…59/cureus.15111

2. drop jump(English)

   • CMJ, CMJA, PT
   • Exercise & Training
   • https://doi.org…jsm.2007.035113