oncosphere
/ˈɒŋkə(ʊ)sfɪə/(also onchosphere) Zoology
noun
A tapeworm embryo or larva in the form in which it hatches from the egg, having a small, oval body bearing three pairs of chitinous hooks for attachment to the tissues of the intermediate host; a proscolex, a hexacanth.
Origin
Late 19th century; earliest use found in American Naturalist. From ancient Greek ὄγκος barb + sphere, after French oncosphère.