Cognomen วัฒนพจน์ (วัฒนพจน์ 
, Watthaphot ) , all over the world, is a very rare last name. The family name วัฒนพจน์ is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname. Also, วัฒนพจน์ is the forename as well as the last name.