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parasitology par·a·si·tol·o·gy (pār'ə-sĭ-tŏl'ə-jē, -sī-)
The study of parasites and parasitism.
the study of animal and plant parasitism as a biological phenomenon. Parasites occur in virtually all major animal groups and in many plant groups, with hosts as varied as the parasites themselves. Many parasitologists are concerned primarily with particular taxonomic groups and should perhaps be considered students of those groups, rather than parasitologists per se; others are interested in parasitism as an evolutionary phenomenon and work with a number of taxonomic groups. The science has a number of branches (e.g., veterinary, medical, or agricultural parasitology).