Flatfish and Righteyed flounder

Flatfish noun - Any of several families of fishes having flattened bodies that swim along the sea floor on one side of the body with both eyes on the upper side.

Righteyed flounder and flatfish are semantically related. In some cases you can replace phrase "Righteyed flounder" with "Flatfish", this terms are similar.

Righteyed flounder noun - Flounders with both eyes on the right side of the head.

Flatfish and righteyed flounder are semantically related. You can use "Flatfish" instead a noun phrase "Righteyed flounder".