| Acronym | Definition |
|---|
| OTB | On the Board |
| OTB | Off-Track Betting |
| OTB | Outside the Box (various companies) |
| OTB | On the Bus (various companies) |
| OTB | On the Bench |
| OTB | Off the Boat |
| OTB | On the Beach |
| OTB | Outside the Beltway |
| OTB | Option to Buy (real estate) |
| OTB | Off to Bed |
| OTB | Obey the Brave (Canadian band) |
| OTB | One Touch Backup |
| OTB | On the Bum |
| OTB | Object Time Base |
| OTB | Offer to Beat |
| OTB | Out-of-the-Box |
| OTB | Open-To-Buy |
| OTB | On the Border (Mexican restaurant) |
| OTB | Occupy the Banks (politics) |
| OTB | Off The Back (used when a racer has been left behind) |
| OTB | Ontario Trillium Benefit (Canada) |
| OTB | Open to Below (construction) |
| OTB | Over the Bridge |
| OTB | Over the Beach |
| OTB | Over-The-Board |
| OTB | On-The-Ball |
| OTB | Only the Best |
| OTB | On The Brink (band) |
| OTB | On-the-Books |
| OTB | Object Test Bench |
| OTB | Only the Bros |
| OTB | OneSAF Testbed Baseline (RDT&E vehicle to develop OneSAF, US Army) |
| OTB | Over the Bars (mountain bikes) |
| OTB | Owning the Technical Baseline |
| OTB | Online Turn Based (chess) |
| OTB | Over Target Baseline (budgeting) |
| OTB | Over the Boards (hockey website) |
| OTB | Organisasi Tanpa Bentuk (Indonesian: formless organization) |
| OTB | Operations Training Branch |
| OTB | One Time Buy |
| OTB | On Target Bonus |
| OTB | Outside the Brick (Lego forums) |
| OTB | Olympus Terumo Biomaterials Corporation (Japan) |
| OTB | Object Transaction Broker |
| OTB | Orbiter Timing Buffer |