Cognomen แก้วสกุล (Glass 
, แก้วสกุล, Kawsakul 
) , throughout the world, is a common last name. The cognomen แก้วสกุล is characteristic of Guernsey, where it is quite a common surname, New Zealand, and the United States. In absolute terms, it is the most numerous in the United States, the United Kingdom, and Germany. Much less frequently, แก้วสกุล is the forename as well as the last name.