The Curse of Scotland is a nickname used for the Nine of Diamonds playing card. The expression has been used at least since the early 18th century, and many putative explanations have been given for the origin of this nickname for the card.

By 1757 the card was described as "commonly called the Curse of Scotland" with the explanation that the epithet refers to Lord Ormistoune, Lord Justice Clerk from 1692 to 1735, who suppressed the Jacobite rising of 1715 and "became universally hated in Scotland". In 18th-century Scotland, the nine of diamonds was sometimes called the "Justice Clerk", and was considered to be the most unlucky card in the pack.

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