platybasia
/ˌplatɪˈbeɪsɪə/Medicine
noun
Flattening of the base of the skull; especially a developmental or acquired abnormality in which there is invagination of the area of the skull around the foramen magnum (basilar impression).
Origin
Late 19th century; earliest use found in Journal of the Royal Anthropological Institute. From platybas- + -ia; compare basi-.