Translation

The Japanese word for "Hornet" is suzumebachi 雀蜂.

  • Vespinae vs. Wasp
    suzumebachi 雀蜂 refers to the subfamily Vespinae. All Vespinae are Wasps, so you can always translate suzumebachi スズメバチ to "Wasp," but some Wasps aren't Vespinae, so you can't always translate "Wasp" to suzumebachi スズメバチ.
Romaji su zu me ba chi
Hiraganaすずめばち
Katakanaスズメバチ
Kanji 雀 蜂
Meaning Sparrow Bee
School Level ✕ 中

Loan-word

The word "Hornet" katakanized would be hōnetto ホーネット.
Romaji hoo ne tto
Katakanaホーネット
Hiraganaほーねっと

Further Reading

Wikipedia: Vespinae (スズメバチ)