Cognomen コイロ (Coiro 
, コイロ) , throughout the world, is quite a rare surname. The surname コイロ is characteristic of Italy, where it is quite a rare surname, Uruguay, and Argentina, where it is a rare surname. Not in comparison with a country's population, it is commonest in Italy, the United States, and Argentina. Very seldom, コイロ is the forename as well as the last name.