Soi (ซอย sɔ̄ːj) is the term used in Thailand for a side-street branching off a major street (Thanon, ถนน). An alley is called a Trok (ตรอก). ==Overview== Sois are usually numbered, and are referred to by the name of the major street and the number, as in `Soi Sukhumvit 4`, `Sukhumvit Soi 4`, or `Sukhumvit 4`, all refer... Found on http://en.wikipedia.org/wiki/Soi