1. covered with or containing mold; having a musty smell or appearance due to dampness
Usage: British spelling; American spelling is ‘moldy’
2. old-fashioned or outdated
Usage: informal; British

Examples

• The bread had gone mouldy after sitting in the damp cupboard.
• She discovered mouldy cheese at the back of the refrigerator.
• The basement smelled mouldy from years of moisture problems.
• His mouldy old ideas about technology needed updating.
• The mouldy books in the attic were beyond saving.
• Don’t eat that fruit if it looks mouldy.