Japanese rice fish; medaka; killifish
A small freshwater fish native to Japan, often kept in aquariums and used in scientific research. The name is widely recognized even by children.
I found some medaka in a nearby rice paddy.
子供のころ、メダカを飼っていた。
When I was a child, I kept medaka.
Katakana spelling is common in biological contexts and everyday use; usually written in kana.
Hiragana spelling is also used, especially in informal or child-oriented writing.
Kanji spelling is occasionally seen but rare; the word is overwhelmingly written in kana.
The name メダカ (medaka) likely derives from 目 (me, 'eye') + 高 (taka, 'high'), referring to the fish's relatively large, upward-looking eyes. The exact historical origin is uncertain.