
1) Brill 2) But 3) Dab 4) Flounder 5) Halibut 6) Holibut 7) Plaice 8) Sole 9) Tonguefish 10) Turbot 
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https://www.crosswordclues.com/clue/flatfish

1) Fish 2) Halibut or sole 3) Marine edible fish 4) Saltwater fish 5) Sole 6) Turbot or plaice 
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https://www.crosswordclues.com/clue/flatfish

 A flatfish is a member of the order Pleuronectiformes of ray-finned demersal fishes, also called the Heterosomata, sometimes classified as a suborder of Perciformes. In many species, both eyes lie on one side of the head, one or the other migrating through and around the head during development. Some species face their left sides upward, some face...
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http://en.wikipedia.org/wiki/Flatfish

• (n.) Any fish of the family Pleuronectidae; esp., the winter flounder (Pleuronectes Americanus). The flatfishes have the body flattened, swim on the side, and have eyes on one side, as the flounder, turbot, and halibut. See Flounder.
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http://thinkexist.com/dictionary/meaning/flatfish/

any of about 600 species of bony, oval-shaped, flattened fishes, such as the flounder, halibut, and turbot.
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http://www.britannica.com/eb/a-z/f/35

Species of fish that have a flat body and both eyes on the same side of the body, includes plaice, sole, dab, turbot and brill
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http://www.encyclo.co.uk/local/20545

Waters:Atlantic and Pacific coasts Description (in water): 'Flatfish' can refer to any member of a species of thin, flat fish that swim on one side; both eyes are located on the side that faces up. Size and color vary depending on the species; the downward-facing side of the fish is always pale and nearly colorless. Description (in market): In general, flatfish have lean white or off-white flesh that's fine-textured and mild in flavor. The skin is edible, and usually quite tasty. ...
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http://www.encyclo.co.uk/visitor-contributions.php
 Flat'fish`  noun  (Zoology)
Flat'fish`  noun  (Zoology) Any fish of the family 
 Pleuronectidæ ; esp., the winter flounder (
 Pleuronectes Americanus ). The flatfishes have the body flattened, swim on the side, and have eyes on one side, as the flounder, turbot, and halibut. See 
 Flounder . 
Found on 
http://www.encyclo.co.uk/webster/F/39

[
n] - sweet lean whitish flesh of any of numerous thin-bodied fish 2. [n] - 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
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http://www.webdictionary.co.uk/definition.php?query=flatfish

Fish that have a flat body with both eyes located on the upper side. Flatfish swim 'sideways' and include 'flounder,' 'halibut,' and 'sole.' 
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https://www.encyclo.co.uk/local/20110
 noun
 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
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https://www.encyclo.co.uk/local/20974

Bony fishes of the order Pleuronectiformes, having a characteristically flat, asymmetrical body with both eyes (in adults) on the upper side. Species include flounders, turbots, halibuts, plaice, and the European soles
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https://www.encyclo.co.uk/local/21221

any fish of the order Heterosomata (Pleuronectiformes), including the halibut, sole, flounder, etc., having a greatly compressed body and swimming on one side, with both eyes on the upper side in the adult.
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https://www.infoplease.com/dictionary/flatfish
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