I thought "dialysis" was a medical treatment for persons with kidney failure.

i must have had some good teachers, i learned that dialysis was a way of treating the blood of people with kidney failure. .
(i had national kidney association as a 'client' when i work as field tech for X, got to see lots of promotional material (and dialysis machines--not in use) while there. i am a compulsive reader.. it used to take the machines 4 minutes to warm up... even boring information is ok for 4 minutes, and add up those 4 minutes, 10, 15 times a in a year...i ended up knowing a fair amount about renal failure!