Cognomen ประโยค (Claus 
, ประโยค 
, Prayok ) , across the world, is a common last name. The last name ประโยค is habitual in Western Europe, particularly Belgium, where it is quite a common surname, Germany, and Luxembourg, where it is quite a rare surname. In absolute terms, it is the most numerous in Germany, the United States, and Belgium. More frequently, ประโยค is the forename as well as the last name.