| FO | fiberoptic; fish oil; foot arthrosis; foramen ovale; forced oscillation; fronto-occipital |
|---|---|
| ORS | olfactory reference syndrome; oral rehydration solution; oral surgery, oral surgeon; Orthopaedic Res... |
| OR | a logical binary relation that is true if any argument is true, and false otherwise; [o]estrogen rec... |
| EPA | eicosapentaenoic acid; empiric phrase association; Environmental Protection Agency; erect posterior-... |
| EPA/RCRA | Environmental Protection Agency Resource Conservation and Recovery Act |