Hotaru is a name of Japanese origin and the meaning of Hotaru is ‘firefly’. Traditionally, the name Hotaru is given to baby boys. Hotaru is a name of a character in the 'Mortal Kombat' fighting games. A person in the world of sports with this name is Hotaru Yamaguchi, a Japanese soccer player and a member of the national soccer team. The name Hotaru started to become popular in the '90s.