Cognomen Siw (Siw 
, シュー 
) , all around the world, is a rare family name. The cognomen Siw is characteristic of Malaysia, where it is quite a rare surname, Singapore, where it is a rare surname, and Norway. Not in comparison with a country's population, this name is the most popular in Malaysia, Japan, and Indonesia. More prevalently, Siw is the forename as well as the last name.