| Abbreviation | Definition |
|---|---|
| OLF | Outta left field |
| OM | Oh, Merde! |
| OM | On My .... |
| OMG | Oh, My God |
| OMGGM | Oh My Goodness Gracious Me |
| OMGM | Oh My Goodness Me |
| OMT | One More Thing |
| OMW | On My Way |
| ONLN | ONLiNe |
| OOF | Out Of the Office |
| OOMA | Object Of My Affection |
| OOO | Out Of Office |
| OOSOOM | Out Of Sight, Out Of Mind |
| OOT | Out Of Time |
| OOTD | One Of Those Days |
| OOTO | Out Of The Office |
| OP | Original Post |
| OP | Out of Place |
| OPT | On Pace To .... |
| ORG | ORIGINAL - As in "Reread my original ? to you." |