Biwa oily gudgeon
A freshwater fish (Sarcocheilichthys variegatus microoculus) endemic to Lake Biwa, Japan. Scientific or field-guide term; not an everyday word.
The Biwa oily gudgeon is a freshwater fish that lives only in Lake Biwa.
Kanji spelling is rare and mostly found in specialized contexts; the word is usually written in kana.
Named after Lake Biwa (琵琶湖) and the Japanese word ひがい (oily gudgeon). The exact derivation is straightforward; the kanji 琵琶鰉 are ateji based on the lake name and fish type.