has part has part has_part characteristic of abnormal tympanic cavity morphology abnormal tegmen tympani morphology 2017-10-25T13:17:15Z any structural anomaly of the thin plate of bone which separates the middle ear (tympanic) cavity from the dura of the middle cranial fossa and forms the roof of the middle ear cavity; it is formed in part by the petrous portion of the temporal bone, and the squamous portion of the temporal bone MPheno.ontology MP:0030321 tympanic cavity