- lumbago (n.)
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- 1690s, from Late Latin lumbago "weakness of loins and lower back," from Latin lumbus "loin" (usually plural), from PIE *lendh- (1) "loin" (source also of Old Church Slavonic ledvije (plural) "loins; soul," Russian ljadveja "loin;" Old English lendenu "loins," German Lende "loin," Lenden "loins").