Family name Kaysyn (Кайсын 
, Каисын , Каисин ) , across the world, is a very rare last name. The surname Kaysyn is habitual in Russia, where it is a very rare surname, Kazakhstan, and Kyrgyzstan. In absolute terms, the name is most common in Russia, Kazakhstan, and the United States. Also, Kaysyn is the forename as well as the last name.