What does Caio mean?
Caio \caio\ as a boys' name. Caio's name origins are Welsh and Latin, and the meaning of Caio is "happy". Caio is a variation of Caeo (Welsh). Caio is also a variation of Cai (Welsh). Caio is also used as a derivative of Caius (Latin) and Gaius (Latin).
Caio is an uncommonly occurring first name for men. Caio is an unusual last name too for both adults and children. (2000 U.S. Census)
Below is a graphed comparison of the usage of Caio and associated names. Popular variation forms of Caio (#unlisted) are Kai (#177 in 2014) and Kay. These boy names were at the apex of their popularity in 2014 (usage of 0.4115%), except for the form Kay which has become less stylish. Kai (#177) is the most contemporarily stylish name for newborns among these. (Top 1000 Birth Names Records, 2014)