Meaning A boy's name of Latin origin, it means "rejoicing or joyous." Origin of Caius Latin Popular Middle Names Alejandro, Atticus, Raphael Pronunciation 🔊 Listen Caius KAYY-ahs Similar Names Jaron Jaryn Jeran Jeren Jerren Jerrin Jerron Joyanna Yoval Jarran Year by Year Popularity of Caius