All abbreviations starting with O
| Term | Full Form | Category |
|---|---|---|
| O | Contour Pattern 
| Others |
| O | form O solenoid
| Others |
| O | Hug
| Others |
| O | Oakland
| Others |
| O | Oasis
| Others |
| O | Oatmeal
| Others |
| O | Obedience
| Others |
| O | Obedient
| Others |
| O | Oben
| Others |
| O | Oberst
| Others |
| O | Object
| Others |
| O | Objectives
| Others |
| O | Obliqueness
| Others |
| O | Oblivion
| Others |
| O | Observation
| Others |
| O | Observed
| Others |
| O | Obvious
| Others |
| O | Occipito
| Others |
| O | Occlude
| Others |
| O | Occult
| Others |
| O | Octant
| Others |
| o | octet
| Others |
| O | Octopus
| Others |
| O | Odd
| Others |
| O | Oddity
| Others |
| O | Odds
| Others |
| O | Odin
| Others |
| O | Odor
| Others |
| O | Of
| Others |
| O | Off
| Others |
| O | Offer
| Others |
| O | Officer
| Others |
| O | Official
| Others |
| O | Offset
| Others |
| O | Often
| Others |
| O | Oh
| Slang |
| O | Ohm
| Others |
| O | Ola
| Others |
| O | Old
| Others |
| O | Oldenburg
| Others |
| O | Oldest
| Others |
| O | Oliver
| Others |
| O | Oluolu
| Others |
| O | Olympics
| Others |
| O | Omaha
| Others |
| O | Omicron
| Others |
| O | Omni
| Others |
| O | Omologato
| Others |
| O | One
| Others |
| O | Ongoing
| Others |