Word Study
renal
CIDE DICTIONARY
renal, a. [L. renalis, fr. renes the kidneys or reins: cf. F. rénal. See Reins.].
Of or pertaining to the kidneys; in the region of the kidneys. [1913 Webster]
OXFORD DICTIONARY
renal, adj. of or concerning the kidneys.
Etymology
F r{eacute}nal f. LL renalis f. L renes kidneys
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