[mil-doo, -dyoo]


Plant Pathology. a disease of plants, characterized by a cottony, usually whitish coating on the surface of affected parts, caused by any of various fungi.
any of these fungi.Compare downy mildew, powdery mildew.
any of similar coatings or discolorations, caused by fungi, as that which appears on fabrics, paper, leather, etc., when exposed to moisture.

verb (used with or without object)

to affect or become affected with mildew.

Origin of mildew

before 1000; Middle English: honeydew, mildew; Old English mildēaw, equivalent to mil- honey (cognate with Gothic milith, akin to Latin mel, Greek méli) + dēaw dew
Related formsmil·dew·y, adjectiveun·mil·dewed, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for mildewed

Historical Examples of mildewed

  • If they mildewed they would be a dead loss to the merchants handling them.

  • Many of the pictures in the gallery were warped and cracked, and mildewed by neglect and damp.

    Art in England

    Dutton Cook

  • And all you've got is that mildewed chaperon, snoring there.

  • I took these out, and discovered a little dress, musty and mildewed.

    Field and Forest

    Oliver Optic

  • "My conscience is mildewed and my temper is blue molded," declared Grace.

British Dictionary definitions for mildewed



any of various diseases of plants that affect mainly the leaves and are caused by parasitic fungiSee also downy mildew, powdery mildew
any fungus causing this kind of disease
another name for mould 2


to affect or become affected with mildew
Derived Formsmildewy, adjective

Word Origin for mildew

Old English mildēaw, from mil- honey (compare Latin mel, Greek mēli) + dēaw dew
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for mildewed



mid-13c., mildeu "honeydew, nectar," from Old English meledeaw "honeydew" (sticky stuff exuded by aphids), from Proto-Germanic compound of *melith "honey" (see Melissa) + *dawwaz "dew" (see dew). Cf. Old Saxon milidou, Dutch meeldauw, German Meltau "mildew."

First element in many cases assimilated to forms of meal (n.2) "ground grain." As a kind of fungus it is first recorded mid-14c., so called from its being sticky and originally growing in plants. As a verb from 1550s. Related: Mildewed.

Online Etymology Dictionary, © 2010 Douglas Harper

mildewed in Science



Any of various fungi or oomycete organisms that form a white or grayish coating on surfaces, such as plant leaves, cloth, or leather, especially under damp, warm conditions. Powdery mildews are important plant diseases usually caused by ascomycete fungi, while downy mildews, including a serious disease of grapevines, are caused by oomycetes.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.