Home › Words › O › oncosphereoncosphereoncosphere means an embryonic form of a tapeworm, enclosed in a spherical membrane armed with six hooks.Among words judged in Lexicurio's Arena, oncosphere ranks #2,710 of 42,752 for Qualifying.EtymologyFrom onco- (“lump”) + -sphere.nounAn embryonic form of a tapeworm, enclosed in a spherical membrane armed with six hooksDefinitions & examples from Wiktionary (CC BY-SA 3.0).