Emily Dickinson Lexicon

LOIN, n. [Sax. lend; G. D. lende; Sw. länd; Dan. lænd; W. clun; Arm. lænenn or loinch; Ir. luan or bleun; L. clunis; G. lehne, support, prop, back. This word seems to be allied to lean, incline.]

The loins are the space on each side of the vertebrae, between the lowest of the false ribs and the upper portion of the ossa ilium or haunch bones, or the lateral portions of the lumbar region; called also the reins.