Oxford Dictionary Adds 'Twerk' to its Vocabulary
PHOTO: Several pop culture words are now part of the Oxford Dictionaries Online.

Dictionaries can have personalities too. The Oxford English Dictionary, which only recently accepted tweet as an official word, seems prudish and outdated compared to the Oxford Dictionaries Online (ODO), which added definitions for phablet, selfie, twerk and several other words to its website on Wednesday.

But rather than say one dictionary is better than the other, Christian Purdy, the director of publicity for the Oxford University Press-USA, said that they're fundamentally different from one another. "The dictionary content in ODO focuses on current English and includes modern meanings and uses of words," he told ABC News. "It's not telling you what the language should be. It's all about how [words] are used."

Several of the new words represent some of the key moments in 2013. 'Bitcoin' skyrocketed in value this year and currently is worth approximately 120 times more than the U.S. dollar. 'Space tourism' is turning from science fiction to reality, thanks to companies such as Virgin Galactic and Mars One.

And like it or not, the Internet is also making a big impact on the English language. Derp is both a noun, meaning foolishness or stupidity, and also an exclamation, often paired with herp (as in 'herp derp'). Srsly is a multipurpose adverb for when writing 'seriously' doesn't cut it.

While it seems like any slang word could make it into ODO, there is a vetting process involved. Angus Stevenson, the head of dictionary projects for ODO, said in a statement, "Each month, we add about 150 million words to our corpus database. ... We use this database to track and verify new and emerging words and senses on a daily basis." He noted that the ODO adds about 1,000 words every year.

Thankfully, YOLO is not one of those words. srsly.

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