How you spell this word – whether referring to fungus or shaping something – depends if you’re in America or not.

American English prefers mold. This extends to its derivatives such as moldy and molding.

British English’s preference is mould, mouldy and moulding. This spelling is favored in the United Kingdom, Australia and New Zealand.

Canada is caught in the middle. Mould generally is taught in schools, but some newspapers, magazines, and websites go with the American spelling of mold.