| Abbreviation | Definition |
|---|---|
| OTSS | On The Safe Side |
| OTT | Over The Top |
| OTTOMH | Off The Top Of My Head |
| OTTOMY | Off The Top Of My Head |
| OTTOOTP | On The Toilet Out Of Toilet Paper |
| OTW | Off The Wall |
| OTX | Off The Xans |
| OTY | Of The Year |
| OU | Over Used |
| OUAT | Once Upon A Time |
| OUAT... | Once Upon A Time... |
| OUG | One Ugly Guy |
| OUGHTA | Ought To |
| OUH | Oh You Haven't! |
| OURAQTGINVU | Oh, You Are A Cutie! Gee, I Envy You |
| OURAQTGINVU | Oh, You Are A Cutie! Gee, I Envy You |
| OVS | Our Very Special .... |
| OW | On Wednesday |
| OW | One word |
| OWC | One Who Cares |