rainbow smelt
A species of smelt (Osmerus mordax dentex) found in northern Japan; the name literally means 'cucumber fish'.
In Hokkaido, rainbow smelt run up the rivers in spring.
Katakana spelling is standard for this fish name; the word is usually written in kana.
Ateji kanji spelling; rarely used in practice.
The name キュウリウオ literally means 'cucumber fish', likely from the cucumber-like smell of fresh specimens.