noun
substitute fish
Refers to using a different, often cheaper or more available, fish species in place of the traditional one in a dish, especially in sushi and sashimi.
回転寿司では、マグロの代用魚としてアカマンボウが使われることがある。
At conveyor-belt sushi restaurants, opah is sometimes used as a substitute for tuna.
代用魚を使うことで、高級魚の味を手頃な価格で楽しめる。
By using substitute fish, you can enjoy the taste of high-grade fish at an affordable price.