Containers with a specific shape used to form things like cakes or metals; also, fuzzy fungi that grow on damp surfaces.
From Old Norse 'mold' meaning 'soft, powdery substance.' The word evolved to mean both a shaped container (from the idea of forming something) and the fungal growth (the old, powdery stuff that grows on things).
The British spelling 'mould' and American 'mold' diverged centuries ago, and they have two wildly different meanings depending on context—a baker's mould is completely different from the mould growing in your bathroom!
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