noun

mildew

MIHL-dyoo

noun

A powdery or fuzzy fungal growth, usually whitish or greyish, that forms on damp surfaces, fabric, or decaying plants.

"The bathroom tiles were spotted with black mildew from the constant steam."

"Leave the tent out to dry properly or it will grow mildew."

verb

To become covered in, or ruin something with, this fungal growth.

"The old curtains had mildewed after years in the damp attic."

How to Use Mildew

Learner’s notes

In plain EnglishA type of fungus that grows on damp things, leaving powdery white or grey patches and a musty smell.

Common mistake

Mildew and mould are closely related and often used loosely, but mildew usually refers to the surface, powdery type found on fabric, paper, and plants, while mould can be more general and grow deeper into a material.

Easily confused with

mould →

Common pairings

mildew stains prevent mildew smell of mildew

Word Forms

mildewed past tense, mildews plural, mildews singular

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Fill the Gap

Can you complete this real example?

The bathroom tiles were spotted with black _____ from the constant steam.

Etymology

From Old English mildēaw, itself a blend of an old Germanic word for "honey" and "dew" — an old poetic image for the sticky, dew-like film fungus can leave behind.