Narwhal (noun)

1. A medium-sized whale that is found in the Arctic waters and is characterized by a long spiral tusk protruding from its head, which is actually an elongated upper left incisor tooth.
2. A marine mammal that is closely related to the beluga whale and is known for its long tusk.

Origin:

The word narwhal comes from the old norse word "nár" meaning corpse and "hvalr" meaning whale. it was first used in the 14th century to describe a type of whale that is found in the arctic waters.

Examples:

1. The narwhal's tusk can grow up to 9 feet long.
2. Narwhals are relatively elusive and are difficult to study in the wild.
3. The narwhal is known for its long tusk, which is actually an elongated upper left incisor tooth.
4. Narwhals are a type of whale that live in Arctic waters.
5. Narwhals are often hunted for their tusks, which are highly valued for decorative and ceremonial purposes.