Dictionaries incorporate new words every year.
Some are pop culture inventions such as jeggings, photobomb and meme. Others, such as emoji and upvote, spring up from technology and social media.
Dictionaries respond by creating definitions for anyone who cares to know what a twitterer is. Thank goodness they do; you can learn what an eggcorn is simply by turning a few pages in your trusty updated dictionary.
Not all newly added words are recent developments. The Oxford English Dictionary June 2015 new words list included autotune, birdhouse, North Korean and shizzle. North Korea was founded in 1948. The initial release of the autotuner audio processor was in 1997.
Before adding a slang term like shizzle, dictionary publishers weigh its current popularity, predicted longevity and other factors. This year alone, the Merriam-Webster Dictionary welcomed about 1,700 new arrivals.