Final answer:
A parasite that kills its host is called a Parasitoid. Parasitoids distinguish themselves from other parasites by typically killing their hosts as part of their life cycle.
Step-by-step explanation:
A parasite that kills its host is more appropriately called a Parasitoid. Unlike typical parasites, parasitoids usually kill their hosts, often as a part of their life cycle. Parasitism, in general, involves an organism (the parasite) that lives in or on another organism (the host) and derives nutrients from it. In this relationship, the parasite benefits while the host is harmed. However, a key distinction is that most parasites do not rapidly kill the host as their reproductive success often depends on the survival of the host long enough to allow the transfer of the parasite or its offspring to a new host. Parasitoids are unique in that the host's death is a necessary part of their life cycle.