| OTT | Notingham VORTAC (VHF Omni-Range navigational station/TACAN station), Nottingham, Maryland USA 
| Others |
| OTT | Object To Test
| Others |
| OTT | Ocean Technology Transition
| Others |
| OTT | Oesophageal Transit Test
| Others |
| OTT | Off The Topic
| Others |
| OTT | Office of Technology Transfer
| Others |
| OTT | Office of Technology Transitions
| Others |
| OTT | Office of Transportation Technologies
| Others |
| OTT | Oldsmobile Toronado Trofeo
| Others |
| OTT | Oldtimer Traktor
| Others |
| OTT | One Time Text
| Others |
| OTT | One True Thing
| Others |
| OTT | One True Threesome
| Others |
| OTT | One-Time Tape
| Others |
| OTT | Online Travel Training
| Others |
| OTT | Open Office Text Template
| Others |
| OTT | OpenDocument Text Template
| Others |
| OTT | Optical Topological Transition
| Others |
| OTT | Optional Team Targeting
| Others |
| OTT | Ottawa
| Others |
| OTT | Ottumwa Terminal Railroad
| Others |
| OTT | Ottumwa Terminal Railroad Company
| Others |
| OTT | Out of The Theatre
| Others |
| OTT | Over the Top Television
| Others |
| OTT | Over The TV
| Others |
| OTT | Over-The-Top
| Others |
| OTT | Overlord Timmy Turner
| Others |
| OTT | Overseas Trained Teacher
| Others |