Anything you regard as ugly, foul, or repulsive, especially in a moral sense.
Gossiping (e.g., “having the dirt on something”).
Guilt or negativity that tarnishes an otherwise lovely thing.
Lack of use (something getting dusty, or having to be dusted off, like an artistic talent). Dirt appearing on a specific part of the body can warn of an undetected malady.
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