mumpsimus /mumpˈsi-məs/

1. A view or opinion stubbornly held, even when shown to be misguided
2. A person holding such a view, or one adhering stubbornly to old ways

• horsepond
• horseponds
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• horse race
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• horseradish
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• horseradish sauce
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• horseradish tree
• horseradish trees
• horse rake
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• horse-rider
• horse-riders
• horse-riding
• horses
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• horseshoe
• horseshoe bat
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• horseshoe crab