Cognomen Сайкс (Sykes 
, Sikes , Сайкс 
) , all over the world, is a common surname. The cognomen Сайкс is habitual in Northern Europe, particularly Isle of Man, where it is quite a common surname, Guernsey, and the United Kingdom (explore the name in all countries). Not in comparison with a country's population, it is commonest in the United States, the United Kingdom, and Indonesia. Very seldom, Сайкс is the forename as well as the last name.