President Obama and Republican presidential candidate Mitt Romney finish their debate at the University of Denver on Oct. 3. Saul Loeb/AFP/Getty Images hide caption

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In 1961, the publication of Merriam-Webster's Third International Dictionary sparked an uproar with its inclusion of the word "ain't." Flickr User Greeblie hide caption

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Rep. Paul Ryan has made changes to social safety net programs like Medicare and Social Security — often called "entitlements" — a key part of his political agenda. Win McNamee/Getty Images hide caption

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The word "hopefully" has been used in thousands of NPR stories. Stephanie d'Otreppe/NPR hide caption

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Geoff Nunberg says the magic of metonymy helped propel the word "occupy" into the global consciousness. Douglas Araujo de Moura /Occuprint hide caption

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A message honoring Steve Jobs is scrawled on a blacked-out window at an Apple store in Seattle.

Elaine Thompson/AP hide caption

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In the Communist Manifesto, Karl Marx (above) and Friedrich Engels used the German word Klassenkampfen, which translates as "class struggles." Their critics rendered it as "class warfare."

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If It Ain't Broke ... The word "broke" comes from an old use of the word break, meaning "impoverished," says linguist Geoff Nunberg. "It suggests an abiding association between destitution and destruction." iStockphoto.com hide caption

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