Mackerel: A long, slender saltwater fish. The flesh is firm and fatty, with a distinctive savory flavor. The most popular mackerel is the king mackerel, also known as the "kingfish".

Mackerel, King: Also called the "kingfish", this is the most popular variety of mackerel. This fish has a firm, high-fat flesh with a savory flavor.

Mackerel, Pacific: Also called the "chub," this species of Pacific mackerel is also found in the Mediterranean. Like other mackerels, this fish is fatty and has a strong flavor.

Mahi Mahi: Also called "dolphin fish" and "dorado" Although this fish is a dolphin, it is not a mammal. To avoid this confusion, the Hawaiian name "Mahi Mahi" is becoming prevalent. This fish is moderately fat with firm, flavorful flesh. The meat is high in Omega 3 oil.

Marinated - Indicates that the seafood has been cured in an acidic solution, such as vinegar.

Market Steak - Small steak cut from roasts, usually weighing less than 5 ounces apiece. Also called "round."

Market Price - Price as dictated by the fish market. Usually fresh seafood's daily price when sold at a restaurant. This is because prices can fluctuate depending on catch and availability.

Melanosis: Blackening of the shell in crustacea, especially shrimp and some crabs. Melanosis will always appear in time, but it happens much more quickly if product has not been properly handled before freezing.

Milkfish: An important food fish of the Indo-Pacific region that offers a tender, white flesh. Hawaiians use milkfish for making fish cakes and sashimi. Also called "awa."

Mince - Fish pieces left over from filleting and trimming, sieved to remove any bones; used for making minced blocks.

Mollusks: (or Mollusc): a soft bodied animal usually with a shell: either one shell (known as. uni-valve) or two shells (known as gastropods or bi-valve) or no shell (known as cephalopods) See Shellfish.

Molting: The shedding of the exoskeleton of crustaceans in order to grow.

Monkfish: This large low-fat, firm-textured salt-water fish has a mild, sweet flavor similar to lobster. Sometimes referred to as "poor man's lobster." Also called "Angler," "Lotte," "Belly-Fish," "frogfish," "Sea Devil," and "Goosefish."

Moochim: A Korean-style dried fish with soy sauce.

Moreton Bay Bug - A crustacean found in the Northern Half of Australia. They are a species of Slipper Lobster and their scientific name is Thenus orientalis. Moreton Bay Bugs are generally caught commercially as a by-catch of local prawn fisheries by demersal otter trawls and with dredge nets. More info on Moreton Bay Bugs

Morwong - (Nemadactylus macropterus). Average length 30-40 cm, average weight 1.8 kg, but can grow to 60 cm. Found around New Zealand, southern Australia and southern South America. Deep bodies and laterally compressed with one pectoral fin ray elongated. Colour varies with locality from silvery with a blue-green sheen, to silvery black. Distinctive black shoulder band. Small protractile mouth with thick lips. Moderate scales. Known as Tarakihi in New Zealand: most abundant in the cooler waters south of East Cape and around the South Island. Demersal, main depth range 100-250 m. Caught mainly by trawling. Flesh white, medium-firm texture. Suitable for all methods of cooking.

Mullet: This term is used to describe several families of important food fish. In general, they are saltwater fish with a moderate to high fat content and flesh that is tender, white, and firm textured. They have a sweet, nut-like flavor.

Muscle Line - A line of fat running laterally down the center of a fillet.

Muskellunge: A freshwater pike that averages between 10 and 30 pounds. Some specimens, however have reached 60 pounds and up to six feet in length. Muskellunge offers a lean, firm, low-fat flesh.

Mussel: A popular bivalve mollusc with worldwide distribution. There are salt and freshwater varieties. The thin shell means there is more meat compared to the same weight of clams or oysters. The yellow meat has a sweet and delicate flavor.

Muttonfish: A marine fish of the eelpout family found mainly in the Pacific. The flesh is sweet and white and contains very few bones. Also called "ocean pout."