Meaning

verb lessen the strength or flavor of a solution or mixture

verb corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones

adjective reduced in strength or concentration or quality or purity

originFrom Latin dīlūtus, from dīluere (“to wash away, dissolve, cause to melt, dilute”), from dī-, dis- (“away, apart”) + luere (“to wash”). See lave, and compare deluge.

Etymology from Wiktionary, CC BY-SA 3.0