What is parasite definition?

A parasite is an organism that lives off another organism (host) usually harming the host in the process. The parasite benefits from the host's nutrients and energy, sometimes resulting in illness or death for the host. Parasites can be found in various forms such as bacteria, fungi, protozoa, viruses, and animals like lice, ticks, and tapeworms. Some parasites are harmless, while others can cause severe diseases such as malaria, sleeping sickness, and toxoplasmosis.