There are multiple definitions:

1. distal radial fracture(English)

   • one of the most common fractures with a small peak in incidence among young males and an increasing incidence with age among women. Reliable classification is important
   • SFR
   • Injury, Classification
   • https://doi.org…891-021-04473-5

2. dominant resonance frequency(English)

   • Bioengineering
   • https://doi.org…OC.2021.3126493

3. Dynamic Reference Frame(English)

   • either a 4-dimensional spatial mapping framework used in geodesy and surveying, or a tracking tool used in computer-assisted surgery and robotics
   • Surgery, Robotics, Medical imaging
   • https://doi.org…155/2015/478062