Lobe : A rounded projection.
Lobtail : In cetaceans, to slap the flukes on the water's surface, making a loud splash.
Locally common : Uncommon or absent over most of range, but relatively common in one or more specific localities.
Logging : Lying still at or near the surface.
Lunate : Crescent-shaped.
Mass stranding : The stranding of three or more cetaceans.
Median Fins : The unpaired fins - dorsal, and caudal.
Melon : In many toothed whales, the bulging forehead, often containing oil.
Mesopelagic : Living in the midwaters of the open ocean.
Migration : Regular journeys between one region and another, usually associated with breeding and feeding cycles, or seasonal or climatic change.
Mysticeti : A suborder of the Order Cetacea, containing baleen whales only.
Nape : The area along the back between the head and the dorsal
Nasal : Pertaining to the nostrils and the surrounding area.
Nostril : Referring to the physical hole where breathing takes place (in most cetaceans this is referred to as a blowhole.
Notch : V-shaped cut or indentation.