Those M&D words: Veins and Reins

[Monte Davis]

"reins" is the French word for "kidneys," carried over into early modrn
English

"Reins (rānz) pl.n.: 1. The kidneys, loins, or lower back."
http://www.answers.com/topic/reins


Also, compare two translations of Isaiah 11:5 -- 

"And righteousness shall be the girdle of his loins, and faithfulness the
girdle of his reins."
"Also righteousness will be the belt about His loins, And faithfulness the
belt about His waist."
http://bible.cc/isaiah/11-5.htm

If your caffeous humors are not yet stimulating your kidneys, have another
cup.