I. ˈmil-ˌdü, -ˌdyü noun
Etymology: Middle English, from Old English meledēaw honeydew; akin to Old High German militou honeydew
Date: 14th century
1.
a. : a superficial usually whitish growth produced especially on organic matter or living plants by fungi (as of the families Erysiphaceae and Peronosporaceae)
b. : a fungus producing mildew
2. : a discoloration caused by fungi
• mil·dewy -ē adjective
II. verb
Date: 1606
transitive verb
: to affect with or as if with mildew
intransitive verb
: to become affected with mildew