* Kingdom: Animalia (animals)
* Phylum: Chordata (chordates)
* Class: Mammalia (mammals)
* Order: Cetartiodactyla (even-toed ungulates and cetaceans)
* Suborder: Odontoceti (toothed whales)
* Family: Monodontidae (narwhals and belugas)
* Genus: Delphinapterus
* Species: Delphinapterus leucas
So, more specifically, a beluga whale is a toothed whale within the narwhal and beluga family.