The letter Đ
The letter Đ was introduced to Serbo-Croatian by Đuro Daničić, according to Wikipedia. I found that highly amusing, that he introduced the letter that is the first letter in his name.
Wikipedia also claims that he was born Đorđe Popović, and all I can think of is "nah, that can't be right".
That would be like Jebediah Springfield who was born in a cabin that he helped build.
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