There are multiple definitions:

1. electrographic onset(English)

   • SDA

2. exact outline(English)

   • CH

3. essential oil(English)

   • literature data is attesting their anti-viral activity
   • COVID-19
   • Virology, Therapeutic approaches
   • https://doi.org…04.2021.1932629

4. external oblique(English)

   • IO, TSB
   • Sports medicine, Rehabilitation
   • https://doi.org…3/jsr.2019-0052

5. ethylene oxide(English)

   • used as high-level disinfection for gas sterilisation of duodenoscope
   • CRE, MDRO
   • Gastroenterology, Microbiology, Safety and health
   • https://doi.org…ast-2019-000282

6. expert opinion(English)

   • COR, LD, LOE, NR
   • Specialist / expert, Guidelines
   • https://doi.org…acc.2020.11.035