Translation

rainasarasu means "Rhinoceros" in English.
It's a katakanization, a loan-word.

rainasarasu is normally written with katakana, as ライナサラス.
rainasarasu written with hiragana is らいなさらす.
rainasarasu does not have kanji.
Romaji ra i na sa ra su
Katakana
Hiragana

Further Reading

Wikipedia: (Rhinoceros)