Herman Sidney "Eagle" Day was a punter in the National Football League and a quarterback in the Canadian Football League. Eagle Day may also refer to:

• Eagle Day, known in German as Adlertag, the first day of operations in the German Operation Eagle Attack during the Battle of Britain
• "Eagle Day", an episode from the first series of the crime drama Foyle's War
• Eagle Day, the second novel in Robert Muchamore's Henderson's Boys series

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