renal failure vs renal disorder

renal failure and renal disorder both are nouns.

Word	Noun	Adjective	Verb	Adverb
renal failure	Yes	No	No	No
renal disorder	Yes	No	No	No

As nouns, renal disorder is a hypernym of renal failure; that is, renal disorder is a word with a broader meaning than renal failure:

renal failure: inability of the kidneys to excrete wastes and to help maintain the electrolyte balance
renal disorder: a disease affecting the kidneys

Other hypernyms of renal failure include failure, kidney disease, nephropathy, nephrosis.

renal failure (noun)	renal disorder (noun)
inability of the kidneys to excrete wastes and to help maintain the electrolyte balance	a disease affecting the kidneys