Meaning of "narwhale" in the English dictionary

The narwhal, or narwhale, is a medium-sized toothed whale and possesses a large "tusk" from a protruding canine tooth. It lives year-round in the Arctic waters around Greenland, Canada, and Russia. It is one of two living species of whale in the Monodontidae family, along with the beluga whale. The narwhal males are distinguished by a long, straight, helical tusk, which is an elongated upper left canine. The narwhal was one of many species described by Carolus Linnaeus in his publication Systema Naturae in 1758. Like the beluga, narwhals are medium-sized whales. For both genders, excluding the male's tusk, the total body size can range from 3.95 to 5.5 metres; the males are slightly larger than the females. The average weight of an adult narwhal is 800 to 1,600 kilograms. At around 11 to 13 years old, the males become sexually mature; females become sexually mature at about 5 to 8 years old. Narwhals do not have a dorsal fin, and their neck vertebrae are jointed like those of other mammals, not fused as in dolphins and most whales. Found primarily in Canadian Arctic and Greenlandic and Russian waters, the narwhal is a uniquely specialized Arctic predator.