eunuch obsolete medical term eunuch eunuchism http://purl.bioontology.org/ontology/MESH/D005058 http://purl.bioontology.org/ontology/SNOMEDCT/267403002 http://purl.obolibrary.org/obo/DOID_5003 Broadly, the state of being a eunuch, i.e. a male without testes; narrowly, a hypogonadism characterized by the lack of mature male germ cells and testicular hormones. eunuchoidism