| Keyword | Type | See | See also | Notes |
|---|---|---|---|---|
| Ovimbundu | Ethnic group | Mbundu | ||
| Ovulation | Keyword | |||
| Ownership | Keyword | Property | ||
| Oxhöft culture | Keyword | Oksywie culture | ||
| Oxkintok site | Place | |||
| Oxygen | Keyword | |||
| Oxygen in the body | Keyword | |||
| Oyampi | Ethnic group | |||
| Oyana | Ethnic group | |||
| Oyana language | Keyword | |||
| Oyo empire | Keyword | |||
| Oyster industry | Keyword | |||
| Oysters | Keyword | |||
| Ozette site | Place |