swayback

[ swey-bak ]
/ ˈsweɪˌbæk /
Veterinary Pathology

noun

an excessive downward curvature of the spinal column in the dorsal region, especially of horses.

adjective

Origin of swayback

An Americanism dating back to 1865–70; sway + back1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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