- OCZ – a play on the word Overclockers.
- Onkyo – translates as "sound harmony". The Japanese audio company was founded as Osaka Denki Onkyo K.K in 1946.
- Ooyala – the word Ooyala (ఉయ్యల) means 'cradle' in Telugu, as in a "cradle of innovation".
- Oracle – Larry Ellison, Ed Oates and Bob Miner were working on a consulting project for the CIA. The code name for the project was Oracle. The project was designed to use the newly written SQL database language from IBM. The project was eventually terminated but they decided to finish what they started and bring it to the world. Later they changed the name of the company, Relational Software Inc., to the name of the product.
- Ornge – new name (2006) for Ontario Air Ambulance, chosen to reflect the orange color of its aircraft. It was intended to provide a unique branding but the ornge.com misspelling was already used by an advertising portal.
- Osram – from osmium and wolfram.
Read more about this topic: List Of Company Name Etymologies