Linguist Geoff Nunberg finds that in the film Lincoln, screenwriter Tony Kushner oscillates between old and modern meanings of "equality." DreamWorks/Twentieth Century Fox hide caption

There are those who say the phrase "the whole nine yards" comes from a joke about a prodigiously well-endowed Scotsman who gets his kilt caught in a door. iStockPhoto hide caption

Geoff Nunberg says that, like a lot of the Britishisms peppering American speech these days, "spot on" falls somewhere in the blurry region between affectation and flash. Zdenek Ryzner/iStockphoto.com hide caption

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

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

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

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

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

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

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."