Translation

sunēku means "Snake" in English.
It's a katakanization, a loan-word.

sunēku is normally written with katakana, as スネーク.
sunēku written with hiragana is すねーく.
sunēku does not have kanji.
Romaji su nee ku
Katakana
Hiragana

Orthography Notes

Synonyms

Scientific name: Serpentes.

Further Reading

Wikipedia: ヘビ (Snake)