There are multiple definitions:

1. Senior Environmental Employment(English)

   • EPA
   • Environment

2. series elastic element(English)

   • PEE
   • Physiology

3. selective enamel-etch(English)

   • CQ, DC, FTIR, PA, POS, SBU, SE, TE, TPO, μTBS
   • Materials science, Dentistry
   • https://doi.org…ent.2013.07.007