Last name Sergay (Sergay 
, Сергай 
) , in the world, is a very rare family name. The cognomen Sergay is characteristic of Armenia, where it is a rare surname, Ukraine, where it is a very rare surname, and South Africa. Measured by absolute frequency, it is commonest in the United States, Ukraine, and South Africa. Also, Sergay is the forename as well as the last name.