Raika

German borrowing of Rajka as well as a German variant of Reika.

Variant transcription of Bulgarian Райка (see Rayka).

From Japanese 雷 (rai) meaning "thunder" combined with 華 (ka) or 花 (ka) both meaning "flower". Other kanji combinations are possible.

A famous bearer is Raika Fujii, a Japanese former synchronized swimmer.

In old persian language and Zoroastrian culture and Gilaki dialects, Raika was the title of boys who assisted the persian prince the kings sons throughout the day, during parades and other daily occasions. The Raikas spent the most times with the prince and they were usually the sons of the Royal families such as Royal governors or ministers. They also walked in front of the Prince during official ceremonies.
There are other versions of the name in other languages such as Japanese and Kurdish and east European, where the name could be masculine or feminin depending on the culture. However the oldest proven text of the name Raika appears in the ancient epic Book of Kings Shahname and the ancient Mazandaran and Gilak cultures and languages.
More resources can be found in Dehkhoda persian Encyclopedia, Alavi persian dictionary and the Aryanpour Persian Encyclopedia on the internet or in libraries.

Variant of Raica.