In the entire world, ארנאו (Arnau 
, ארנאו 
) is quite a rare boy's given name. The forename ארנאו is characteristic of Andorra, where it is quite a common masculine name, Spain, where it is quite a rare boy's name, and Paraguay. In absolute terms, it most frequently occurs in Spain, the Democratic Republic of the Congo, and Paraguay. Also, ארנאו is the last name as well as the forename.