Antonyms That Starts with O, Opposites with O
| Words | Antonyms |
| Occasionally | Frequently |
| Other | Same |
| Out | In |
| Odd | Even |
| Open | Closed |
| Obvious | Obscure, ambiguous |
| Occult | Intelligible, transparent |
| Outside | Inside |
| Offspring | Ancestor, forefather |
| Oracular | Lucid, distinct |
| Odious | Engaging, fascinating |
| Often | Seldom |
| Old | Modern |
| Over | Under |
| Ornamental | Unseemly, plain |
| Ordain | Revoke, abolish |
| Open | Closed |
| On | Off |
| Obstruct | Hasten, encourage |
| Outrage | Praise, favour |
| Opaque | Transparent, bright |
| Outskirts | Centre |
| Ordinary | Special |
| Occupied | Vacant |
| Order | Mess |
| Outbreak | Compliance, subjection |
| Off | On |
| Opponent | Supporter |
| Offensive | Docile, compliant |
