The term MONODON MONOCEROS is a combination of two words, Monodon and Monoceros, which refer to the NARWHAL, a species of whale found in the Arctic Ocean. Monodon is Latin for 'one tooth, ' referring to the NARWHAL's long tusk, while Monoceros is Greek for 'one horn, ' also referring to the NARWHAL's tusk. The NARWHAL is a medium-sized whale that can grow up to 17 feet in length and weigh up to 3, 500 pounds. It is known for its distinctive tusk, which can reach up to 10 feet in length and is used for sensing its environment and for fighting.