an extra amount of something, such as time or money, that you allow because there might be a mistake in your calculations

When archaeologists date objects that are thousands of years old, they allow a margin of error of several hundred years. 考古学家在测定有数千年历史的物体的年代时，会允许有几百年的误差。

The British government estimates that its borrowing requirement this year could reach £150 billion, subject to a wide margin of error. 政府预计今年借款将达1500亿英镑，此数额会有较大误差。