Cognomen Косо (Koso 
, Coso 
, Косо 
) , all around the world, is a common surname. The family name Косо is habitual in Pakistan, where it is quite a common surname, Bosnia and Herzegovina, and Serbia, where it is quite a rare surname. In absolute terms, it is commonest in Pakistan, Philippines, and Serbia. Very seldom, Косо is the forename as well as the last name.