Save Gender Masculine Usage Dutch (Rare), Limburgish (Rare) Pronounced Pron. /ˈkɔi̯/ [key·simplify] Other Forms FormsKoj, Koy Meaning & History Meaning uncertain. It might be a combination of Cornelis or Cornelius with a name that starts with J-, such as Jan 1. At least, that appears to have been the case for the Limburgian soccer player Coy Koopal (1932-2003).