There are multiple definitions:

1. ozone depleting substance(English)

   • Environment

2. oculus dexter et sinister(Latin)

   • right and left eye
   • OS, OD

3. osmotic demyelinating syndrome(English)

   • develops secondary to rapid correction of hyponatremia and involves both pontine and extra-pontine myelinolysis. Dyselectrolytemia, especially hyponatremia is a common occurrence in hospitalized patients, and a number of dreaded complications arise out of the disorder itself and its treatment
   • ICU, EPM, pNa
   • Critical Care, Sodium, Clinical chemistry
   • https://doi.org…972-5229.152760

4. octadecyl silane(English)

   • refers to a procedure that involves fast liquid–liquid extraction
   • HPLC
   • Biochemistry
   • https://doi.org…032710801934601