| Glossary Term starting with M |
| Search SeaLifeBase |
| Mackerel sharks |
| Mackerels |
| Macro- |
| Macro-algae |
| Macrobenthos |
| Macroclimate |
| Macrofauna |
| Macrophagous |
| Macrophthalmia |
| Macrophyte |
| Macrophytes |
| Macroplankton |
| Macrosmatic |
| Madeira |
| Madura anchovy |
| Mahseer |
| Maiden |
| Mainframe |
| Mainstream flow |
| Maintenance food consumption |
| Makassar fish |
| Makassar Strait |
| Malacca Strait |
| Malar |
| Malar thorns |
| Malassol |
| Mam-ruot |
| Mammalia |
| Mammose |
| Mandible |
| Mandible length |
| Mandibular symphysis |
| Manefishes |
| Mangrove |
| Mannitol |
| Manta rays and devil rays |
| Many deep passes/open atoll |
| Map |
| Marbled |
| Marbled catfishes |
| Marblefishes |
| Margin |
| Marginal habitat |
| Marginaria |
| Mariculture |
| Marinade |
| Marinate |
| Marine |
| Marine notch |
| Marine Protected Area |
| Marine realm |
| Marine Research Section |
| Marine Science Institute of Andalusia (ICMAN) |
| Marine snow |
| Marinerad stekt sill |
| Marinoitu silakkarulla |
| Mark-recapture study |
| Marked |
| Marketable size |
| Marsh |
| Marsupium |
| Masculinisation |
| Mass selection |
| Mating |
| Mating event |
| Mating scars |
| Mating system |
| Matje cured herring |
| Matje herring |
| Matriachal family |
| Matriarch/patriarch family |
| Matrix |
| Matroclinous inheritance |
| Matrotrophic viviparity |
| Matthiessen's ratio |
| Mattie |
| Maturation |
| Maturity |
| Matutinal |
| Mauthner's axon |
| Maw bladder |
| Maxilla |
| Maxillary |
| Maxillary extension |
| Maxillary length |
| Maximum age |
| Maximum economic yield |
| Maximum equilibrium catch |
| Maximum length |
| Maximum potential yield |
| Maximum standing crop |
| Maximum sustainable yield |
| Maximum weight |
| Maximum yield-per-recruit |
| Meander |
| Mechano-receptor |
| Meckel's cartilage |
| Medial |
| Medial cartilage |
| Medial view |
| Median |
| Median effective concentration |
| Median fin |
| Median fins |
| Median length |
| Median lethal concentration |
| Median predorsal scales |
| Median valley |
| Medicated feed |
| Mediolateral |
| Mediterranean cure |
| Mediterranean Sea |
| Medithermal |
| Medulla oblongata |
| Medusa |
| Medusafishes |
| Megadiversity countries |
| Megalopa |
| Megamouth sharks |
| Megaplankton |
| Meikotsu |
| Meiobenthos |
| Meiofauna |
| Meiolecithal |
| Meiosis |
| Meji |
| Melanesia |
| Melanin |
| Melaniridosome |
| Melanistic |
| Melanocyte |
| Melanonids |
| Melanophore |
| Meltwater |
| Membrane |
| Memorial University, Department of Biology, Newfoundland |
| Memphis State University Museum of Zoology, Tennessee |
| Menhadens |
| Menisicus |
| Mental |
| Mental barbel |
| Menu |
| Merchantable |
| Mere |
| Meristic |
| Meristic characters |
| Merluccid hakes |
| Mermaid |
| Mermaid's purse |
| Mero- |
| Meroblastic |
| Meromictic |
| Meropelagic |
| Meroplankton |
| Mersin |
| Mesentery |
| Mesethmoid |
| Mesh gauge |
| Mesh selection |
| Mesh size |
| Mesiad |
| Mesial |
| Meso- |
| Mesocoracoid |
| Mesohaline |
| Mesolecithal |
| Mesonephros |
| Mesopelagic |
| Mesophythmile |
| Mesopterygium |
| Mesorchium |
| Mesosaline |
| Mesothelial |
| Mesotrophic |
| Mesovarium |
| Meta- |
| Metabolic rate |
| Metabolism |
| Metacentric |
| Metadata |
| Metadatabase |
| Metalimnion |
| Metamere |
| Metamerism |
| Metamorphosis |
| Metencephalon |
| Metonym |
| Metric ton |
| Micro-climate |
| Microatoll |
| Microatolls |
| Microbenthos |
| Microencapsulated diets |
| Microfauna |
| Microhabitat |
| Micronesia |
| Microorganisms |
| Microphagous |
| Micropredator |
| Microprobe analysis |
| Micropyle |
| Microsatellite |
| Microsmatic |
| Microsquamose |
| Microtag |
| Mid-brain |
| Mid-oceanic ridge |
| Midbrain |
| Middle Atlantic Bight |
| Midgut |
| Midocean ridge |
| Midwater |
| Midwater pair trawl |
| Midwater trawl |
| Midwestern State University |
| Miettes |
| Migaki nishin |
| Migrating |
| Migration |
| Mild cured fish |
| Mild smoked fish |
| Milker herring |
| Milkfish |
| Milleporine |
| Milt |
| Milt sauce |
| Milter |
| Milwaukee Public Museum, Wisconsin |
| Mimetic |
| Mimic |
| Minced fish |
| Minimum biological acceptable level |
| Minimum landing size |
| Minimum mesh size |
| Minimum size |
| Minimum Viable Population |
| Minnow |
| Minnows or carps |
| Minor commercial |
| Miocene |
| Mirin |
| Misidentification |
| Misreporting |
| Mississippi Museum of Natural History, Mississippi |
| Mississippi State University, Mississippi |
| Missouri Department of Conservation, Missouri |
| Mitochondria |
| Mitochondrial DNA |
| Mitosis |
| Mixed fishery |
| Mixohaline |
| Mixolimnion |
| Mixoplankton |
| Mixosaline |
| Moat |
| Moat and depression |
| Modal |
| Modal size |
| Mode |
| Model population |
| Modem |
| Moist pellet |
| Mojama |
| Mojarras |
| Molar |
| Molariform |
| Molas |
| Mollusca |
| Molluscs |
| Moluha |
| Molukka Sea |
| Monandric |
| Monandry |
| Monikendammer |
| Monk |
| Mono- |
| Monocotyledoneae |
| Monoculture |
| Monocyclic fish |
| Monoecious |
| Monogamy |
| Monognathic |
| Monomictic |
| Monomorphic |
| Monophagous |
| Monophyletic |
| Monosex |
| Monospecific |
| Monospondylous |
| Monospondylous precaudal vertebrae |
| Monospondylous-diplospondylous transition |
| Monotelic |
| Monothetic key |
| Monotypic |
| Monotypy |
| Montane |
| Moochim |
| Mooching |
| Mooneyes |
| Moonfish |
| Moonfishes or fingerfishes |
| Moorish idol |
| Moray eels |
| Morid cods |
| Morph |
| Morphology |
| Morphometric |
| Morphometric character |
| Morphometric characters |
| Mortality |
| Morula |
| Morwongs |
| Moss Landing Marine Laboratories, California |
| Mother ship |
| Mother-of-pearl |
| Mottled |
| Mountain processes |
| Mouth |
| Mouth brooder |
| Mouth brooding |
| Mouth width |
| Mozambique Channel |
| MS-222 |
| Muciferous |
| Mucin |
| Mucophagy |
| Mucosal fold |
| Mucous canal |
| Mucous gland |
| Mucous membrane |
| Mucronate |
| Mucus |
| Mud |
| Mud fish |
| Mud taste |
| Muddy flavour |
| Mudminnows |
| Mullets |
| Multicuspid |
| Multicuspidate |
| Multimedia system |
| Multiserial |
| Multitasking |
| Multivoltate |
| Muria |
| Murphy's Law |
| Murray State University, Kentucky |
| Musci |
| Musée d'Histoire naturelle, La Chaux-de-Fonds, Switzerland. |
| Musée d'Histoire naturelle, Neuchatel, Switzerland |
| Musée Guimet d'Histoire naturelle de Lyon |
| Musée Océanographique, Monaco |
| Musée royal de l'Afrique centrale, Tervuren |
| Musée zoologique de l'Université Pasteur et de la Ville de Strasbourg |
| Museo civico di Storia naturale "Giacomo Doria", Genova, Italy |
| Museo civico di Storia naturale, Carmagnola, Italy |
| Museo civico di Storia naturale, Milano |
| Museo civico Storia naturale, Verona, Italy |
| Museo de Ciencias Naturales |
| Museo di Storia naturale dell'Università, Firenze, Italy |
| Museo Nacional de Ciencias Naturales, Madrid |
| Museu Bocage, Lisboa |
| Museu de Biologia, Universidad Central de Venezuela |
| Museu de Zoologia, Universidade de Sao Paulo, Brazil |
| Museu municipal do Funchal (Natural History), Madeira, Portugal |
| Museul de Istorie Naturala "Grigore Antipa" |
| Muséum d'Histoire naturelle, Bordeaux |
| Muséum d'Histoire naturelle, Geneve |
| Muséum d'Histoire naturelle, La Rochelle |
| Muséum d'Histoire Naturelle, Saint-Denis, Ile de La Réunion, France |
| Museum für Naturkunde der Humboldt-Universität, Zoologisches Museum, Berlin |
| Muséum national d'Histoire naturelle, Paris |
| Museum of Natural History, Wroclaw University, Wroclaw, Poland |
| Museum of Southwestern Biology, University of New Mexico, Albuquerque |
| Museum of the Institute of Marine Biology, National Sun Yat-Sen University |
| Museum of Zoology, Lund, Sweden |
| Museum of Zoology, University of Bergen |
| Mustard herring |
| Mutagen |
| Mutualism |
| Myelenocephalon |
| Myelin |
| Müllerian mimicry |
| Myomere |
| Myomere count |
| Myomere formula |
| Myomeres |
| Myoseptum |
| Myotome |
| Myriapoda |
| Mysids |
| Myxopterygium |