There are multiple definitions:

1. upper limb disorder(English)

   • RSI in UK
   • RSI

2. upper limb disability(English)

   • SAMP
   • Musculoskeletal system, Pain, Disability
   • https://doi.org…ksp.2021.102428

3. ubiquitin-like domain(English)

   • UAF1, UBD, UBZ, UFB, UIM, USP1
   • Molecular biology
   • https://doi.org…101.2014.956475