- frijoles (n.)
- Mexican kidney beans, 1570s, from Spanish frijoles (plural) "beans," from Latin phaseolus, phaselus "kidney bean," from Greek phaselos a name for a kind of bean.
- kidney (n.)
- early 14c., of unknown origin, originally kidenere, perhaps a compound of Old English cwið "womb" (see bowel) + ey "egg" (see egg (n.)) in reference to the shape of the organ. Figurative sense of "temperament" is from 1550s. Kidney bean is from 1540s, so called for its shape.