Other
- SO, Sony or Sony Ericsson's mobile phones of NTT DoCoMo in Japan
- Stellated octahedron
- S.O. refers to members of the Secular Oratory of the Oratory of St. Philip Neri whilst "C.O." for members of the Congregation
- shell-on shrimp
- So (dairy product), a type of dairy products made in ancient Japan
Read more about this topic: SO