blue mold

noun

1. Also called green mold. any fungus of the genus Penicillium, which forms a bluish-green, furry coating on foodstuffs inoculated by its spores.
2. Plant Pathology.
   1. a disease of plants, characterized by necrosis of leaves or fruit and the growth of bluish or grayish mold on affected parts, caused by any of several fungi, as of the genus Penicillium or Peronospora tabacina.
   2. downy mildew ( def 2 ).

Word History and Origins

Origin of blue mold¹

First recorded in 1655–65

Example Sentences

Blue mold type from Dorsetshire; crumbly, sharp; made in flat forms.

From Project Gutenberg

Sometimes when the skin of a rotten apple has been broken you will find in the broken place a blue mold.

From Project Gutenberg

Bread also sometimes has this blue mold; at other times bread has a black mold, and yet again a pink or a yellow mold.

From Project Gutenberg

The same blue mold that grows on bread often attacks apples that have been slightly bruised; it cannot pierce healthy apple skin.

From Project Gutenberg

Moisten a piece of bread, then dip a match or a pin into the blue mold on a lemon, and draw the match across the moist bread.

From Project Gutenberg