Ian Prior may refer to:

• Ian Prior (cricketer) (1930–2007), English cricketer
• Ian Prior (rugby union) (born 1990), Australian rugby union player

• Southern Theater
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• Southern theaters of the American Revolutionary War
• Southern Theatre Command
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• Southern Thickbilled Lark
• Southern Thick Billed Lark
• Southern thickbilled lark
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• Southern tightcoil
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• Southern tomato pie
• Southern Toussian