mildew
n.a type of mold that grows on damp surfaces like walls, ceilings, or clothes. It usually looks like a white or gray powdery film.
n.a type of mold that grows on damp surfaces, typically appearing as a white or gray powdery coating.
“Mildew grows quickly in the damp bathroom.”
“The landlord had to hire a professional to remove the mildew from the basement walls before the new tenants moved in.”
“While mildew is generally less dangerous than its toxic counterparts, it can cause significant structural damage to wood and fabric if left untreated in a humid environment.”
From Middle English myldew, from Old English meledēaw, mildēaw, from Proto-West Germanic milidauw, from mili (“honey”) + *dauw (“dew”). Compare West Frisian moaldau, Dutch meeldauw, German Mehltau. More at dew.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.