kyphosisPronunciation: /kʌɪˈfəʊsɪs/Definition of kyphosis noun [mass noun] Medicine excessive outward curvature of the spine, causing hunching of the back. Compare with lordosis.Derivatives kyphoticPronunciation: /-ˈfɒtɪk/ adjective Origin: mid 19th century: from Greek kuphōsis, from kuphos 'bent, hunchbacked'kyphosis in other Oxford dictionaries Definition of kyphosis in the US English dictionary