"Engawa" is a part of fish meat and one of the toppings of sashimi or sushi. It means a muscle of flatfish or righteye flounder for moving its fins, and is popular for its crunchy feeling on the tongue. The name comes from the fact that its shape looks like "engawa"which is a veranda of a Japanese house.
When people say "engawa" for a sushi topping, it usually means 'engawa of flatfish.'
Since the amount of engawa part obtainable from one flatfish is limited, engawa is more expensive than white meat. If sushi is provided under the name of "engawa" at a low price at a conveyor belt sushi bar, substitute fish such as Reinhardtius hippoglossoides or Atheresthes evermanni are used. Engawa of righteye flounder is regarded as inferior in flavor to that of flatfish, but some people prefer its rich, fatty taste.