noun
sturgeon
Refers to sturgeon, especially the green sturgeon (Acipenser medirostris). Commonly written in katakana.
チョウザメの卵がキャビアになります。
Sturgeon eggs become caviar.
The word is a compound of 蝶 (chō, 'butterfly') and 鮫 (same, 'shark'), but the exact origin is uncertain; it may refer to the fish's shape or appearance.