Shougen 【生源】2 The Japanese surnames etymology dictionary.
② variant of 雷 . In Fukuoka-ken Fukuoka-shi Fukuoka-ken Itoshima-shi It tells that the pronunciation of thunder (rye) surname changed from "thunder" of Rai San. Estimated in the Edo period. Raiyama is a place name with a record since the Edo period. 雷 reference.