There are multiple definitions:

1. stationary wavelet transform(English)

   • CWT, DWT
   • Wavelets, Transform

2. septal wall thickness(English)

   • MFS, PWT, RWT, WT
   • Cardiology
   • https://doi.org…5273(83)90190-0

3. [myocardial] systolic wall thickening(English)

   • expressed as a percentage of the end-diastolic value
   • WT
   • Cardiology, Ratio-based metric
   • https://www.ncb…les/PMC2717065/

4. standing with toe-extension(English)

   • APSI, MLSI, NS, OSI
   • Musculoskeletal system, Sports medicine, Rehabilitation
   • https://doi.org…al.pone.0041539
   • https://www.jos…t.2003.33.8.468