Cognomen Eoy (Eoy 
) , in all the world, is a rare surname. The family name Eoy is habitual in South-eastern Asia, particularly Philippines, where it is a very rare surname, Indonesia, and Malaysia, where it is an extremely rare surname. Measured by absolute frequency, it is the most numerous in Indonesia, Philippines, and India. Much less frequently, Eoy is the forename as well as the last name.