Cognomen Киаран (Ciaran 
, Ciarán 
, Киаран) , throughout the world, is a rare family name. The family name Киаран is habitual in Ireland, where it is quite a rare surname, Uruguay, where it is a rare surname, and Hungary. Measured by absolute frequency, it is the most numerous in Ireland, Spain, and Uruguay. Much more prevalently, Киаран is the forename as well as the last name.