Translation

The Japanese word for "Whale" is kujira クジラ.

Romaji ku ji ra
Hiraganaくじら
Katakanaクジラ
Kanji 鯨
School Level 中

Loan-word

The word "Whale" katakanized would be hoēru ホエール.
Romaji ho ee ru
Katakanaホエール
Hiraganaほえーる

Further Reading

Wikipedia: Whale (鯨)