lordosis
noun
an abnormal forward curvature of the spine in the lumbar region, resulting in a swaybacked posture.
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Most professional contortionists are, in fact, simply persons born with congenital atrophic/dystrophic conditions of major recti, or with acute lordotic flexion of the lumbar spine, or both.
From The New Yorker ● Feb. 28, 2011