sitio-, siti-, sito-, sit-, -sitia +

1. Symbiosis in which one population (or individual) adversely affects the other, but cannot live without it: Parasitism is the interaction between two organisms whereby one of them, the parasite, benefits at the cost of the host.
2. Infection or infestation with parasites: Jane wondered why her favorite plant was dying and then she saw that it had a bad case of parasitism.
3. Etymology: "a hanger-on, a toady, a person who lives on others", from Middle French (about 1400 to 1600) parasite; from Latin parasitus, from Greek parasitos, "person who eats at the table of another"; from para-, "beside" + sitos, "food".

The scientific meaning of "animal" or "plant that lives on others" is first recorded in 1646.

Infection or infestation with a parasite or parasites: Greg found a book on parasitization which he could use in a report on parasites in his biology class.

To live on or in a host: Such organisms as tapeworms, roundworms, and protozoans parasitize such as, a parasite their hosts (animals or plants) in order to live. .

Referring to something that is caused by parasites: Some diseases, like tick-borne encephalitis and plague, are characterized as being parasitogenic afflictions.

An organism that is a parasite during part of its life cycle: An insect, particularly a wasp, is a parasitoid in that it completes its larval growth inside a host of another insect, and finally kills it., and then is then free-living as an adult organism.

An expert in parasitology: Dr. Smart was a parasitologist and was the best specialist in the field of parasites at the university.

The science or study of parasites and parasitism: Parasitology is a field of biology that specializes in parasites, particularly those of animals and plants.

An irrational dread of parasites: The middle-aged Mrs. Thompson went to her family doctor yet again describing the symptoms of an infestation being under her skin or inside her body, but after being thoroughly examined, the doctor didn't find any such disorder and diagnosed her as having parasitophobia!

A parasite city; a city that is overdeveloped and economically non-productive. In the article, David read about a parasitopolis, a metropolis that had developed to an excessive degree and not productively generative.

Infection or infestation with parasites: Sally was diagnosed with a very bad case of intestinal parasitosis which had to be treated in hospital.

A substance that havs a special affinity for parasites: A parasitotrope designates an active ingredient, a substance or agent, or an organism that has a certain attraction for parasites.

The affinity of a drug for infective parasites: Parasitotropy depicts the attraction of certain substances for parasites, but also includes micro parasites that infect larger parasites.

A parasitic plant: A phytoparasite can be any parasitic vegetable organism or species.

A false parasite: A pseudoparasite may be either a commensal or a temporary parasite (the latter being an organism accidentally ingested and surviving briefly in the intestine).

A pseudoparasite can be an object or organism that resembles or is mistaken for a parasite.

In botany, descriptive of a plant that gets food from a host but also contains chlorophyll and is capable of photosynthesis: Mistletoe is considered to be semiparasitic which thrives on a host plant and also undergoes photosynthesis.