Spermaceti whale. The sperm whale (Physeter macrocephalus), or cachalot, is the largest of the toothed whales and the largest toothed predator. It is the only living member of genus Physeter. Mature males average at 52 feet in length but some may reach 67 feet, with the head representing up to 1/3 of the animal's length. The sperm whale can be found anywhere in the open ocean. From the early 18th century through the late 20th the species was a prime target of whalers. The head of the whale contains a liquid wax called spermaceti, from which the whale derives its name. Spermaceti was used in lubricants, oil lamps, and candles. Ambergris, a waste product from its digestive system, is still used as a fixative in perfumes.