a. [ L. diluens, p. pr. diluere. See Dilute. ] Diluting; making thinner or weaker by admixture, esp. of water. Arbuthnot. [ 1913 Webster ]
n. 1. That which dilutes. [ 1913 Webster ]
2. (Med.) An agent used for effecting dilution of the blood; a weak drink. [ 1913 Webster ]
There is no real diluent but water. Arbuthnot. [ 1913 Webster ]