Surname Sín (秦 
, Signe 
, Sín 
) , all over the world, is a prevalent last name. The family name Sín is characteristic of China, where it is a common surname, Cameroon, where it is quite a common surname, and France, where it is a rare surname. In absolute terms, the name is most common in China, Cameroon, and Philippines. Very seldom, Sín is the forename as well as the last name.