DictionarymildewFungal growth
noun / verb

mildew

MIL-doo/ˈmɪlduː/

A thin layer of fungus that grows on damp surfaces.

Powdery mildew spreads across the damp green leaf near the shaded wall.

Thin white-gray powdery mildew spreads across damp green leaf beside humid shaded wall, close fungal growth.
Etymology

Old English meledeaw meant “nectar, honeydew,” rather than fungal growth. The name was presumably transferred to fungus because it too was sticky and grew on plants.

In context

Truthly1:14
The lid of the coffin had been smashed under the weight and damp soil had poured inside. It was half rotted and full of mildew
Every Incorrupt Saint Science Can't Explain

More examples

  • The towels mildewed after being left in a wet pile.
  • She notices a musty smell and spots of mildew.
  • Good airflow helps keep stored fabrics from mildewing.

Forms

mildew · mildews · mildewed · mildewing

Similar words

mold
A broader term for many kinds of surface-growing fungi.
fungus
Fungus is the broad organism category; mildew is a particular thin surface growth.