mildew

/ˈmɪlˌdu/
noun
  1. A thin, whitish or grayish fungus that grows on plants, paper, cloth, or other surfaces in damp, warm conditions.
    • Mildew ruined the pages of the book stored in the basement.
    • The old shower curtain was covered in black mildew.
    • If you see mildew on your houseplants, move them to a drier spot.
Synonyms
verb
  1. To become covered or affected by mildew.
    • The farmer worried that the wheat would mildew after the heavy rains.
    • The towels will mildew if you leave them in a wet pile.
    • Leather shoes can mildew quickly in a damp closet.
What does "mildew" mean? | whatsthatwordmean | whatsthatwordmean