Helminthology is the study of parasitic worms (helminths), while helminthiasis describes the medical condition of being infected with helminths. Helminthology deals with the study of the taxonomy of helminth and the effect on their hosts.
The origin of the first compound of the word is from the Greek ἕλμινς - helmins (root: helminth-), meaning "worm".
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^Maurice Ernst (1910) (in German), Oxyuris vermicularis (thethreadworm
A treatise on the parasite and the disease in children and adults, together with the particulars of a rapid, harmless and reliable cure, London: Ernst Homeopathic Consulting Rooms and Dispensary