Ringer's solution

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An aqueous solution of the chlorides of sodium, potassium, and calcium that is isotonic to animal tissue and is used topically as a physiological saline and, in experiments, to bathe animal tissues.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an aqueous solution containing the chlorides of sodium and potassium and calcium that is isotonic to animal tissues; used to correct dehydration and (in physiological experiments) as a medium for in vitro preparations