blue mould

noun

1. Also calledgreen mould any fungus of the genus Penicillium that forms a bluish mass on decaying food, leather, etc
2. any fungal disease of fruit trees characterized by necrosis and a bluish growth on the affected tissue: mostly caused by Penicillium species

Example Sentences

Delving in the bottom of the bag, you pull out a neglected piece of bread covered in small bits of white and blue mould.

From BBC

Mrs Squair, 76, said: "It was so bad, even our three-piece suite ended up with blue mould all over it all the way up the side."

From BBC

Bread with white and blue mould on it is fine to cut around and eat but black mould is dangerous.

From BBC

Back in the 1990s, in his first incarnation as a comedian, Newman often played the part of FJ Lewis, a history professor prone to comparing his comedy partner David Baddiel to such things as a "piece of old crust, with, like, blue mould all over it".

From The Guardian

I am ever reminded of blue mould, of stale damp.

From Project Gutenberg