twelve-year-olds swear, but a lot more sixteen-year-olds do. But swearing is very socially salient (we have laws about it!) and not really changing that much. It’s been peaking in adolescence and declining through adulthood for decades. The other trendy linguistic features that we acquire in adolescence (new pronunciations like “bosses” and “shica,” and innovative uses of words like “so” and “like”) are a case of subtle social discernment rather than massive social taboo, and so we tend to keep them as adults.
This age curve is important when we think about when young people start using social media: age thirteen, if you believe the terms of service of most sites and apps, or slightly younger, if you assume that some users lie about their ages. This is right at the beginning of the age range when the language of teens is tremendously influenced by the slang of their peers. Sure, little kids play games and watch videos and even ask questions of voice assistants, but their social lives are still mediated by their families and their reading level. This coincidence of peer influence and social media access means that it’s easy to conflate how the youth are talking now with the tools that they’re using to do so. But every generation has talked slightly differently from its parents: otherwise, we’d all still be talking like Shakespeare. The question is, how much of that is influenced by technology, and how much is the linguistic evolution that would have happened regardless?
The answer seems to be that both happen simultaneously. Researchers from Georgia Tech, Columbia, and Microsoft looked at how many times a person had to see a word in order to start using it, using a group of words that were distinctively popular among Twitter users in a particular city in 2013–2014. As we’d expect, they noticed that people who follow each other on Twitter are likely to pick up words from each other. But there was an important difference in how people learned different kinds of words. People sometimes picked up words that are also found in speech—like “cookout,” “hella,” “jawn,” and “phony”—from their internet friends, but it didn’t really matter how many times they saw them. For rising words that are primarily written, not spoken—abbreviations like “tfti” (thanks for the information), “lls” (laughing like shit), and “ctfu” (cracking the fuck up) and phonetic spellings like “inna” (in a / in the) and “ard” (alright)—the number of times people saw them mattered a lot. Every additional exposure made someone twice as likely to start using them. The study pointed out that people encounter spoken slang both online and offline, so when we’re only measuring exposure via Twitter, we miss half or more of the exposures and the trend looks murky. But people mostly encounter the written slang online, so pretty much all of those exposures become measurable for a Twitter study. The researchers also found that you’re more likely to start using a new word from Friendy McNetwork, who shares a lot of mutual friends with you, and less likely to pick it up from Rando McRandomFace, who doesn’t share any of your friends, even if you and Rando follow each other just like you and Friendy do.
But these networks aren’t formed in isolation: people tend to follow others with similar interests and demographics. One study demonstrating this looked at the geographic spread of a couple thousand words that became massively more popular on Twitter between 2009 and 2012. It found that terms tended to leapfrog from one city to another based on demographic similarity, not just geographic proximity. So slang would spread between Washington, D.C., and New Orleans (both have high proportions of black people), Los Angeles and Miami (high proportions of Hispanic people), or Boston and Seattle (high proportions of white people), but not necessarily the cities in between. For example, the abbreviation “af” for “as fuck” (as in “word maps are cool af”) starts out at low levels in Los Angeles and Miami in 2009, then spreads elsewhere in California, the South, and around Chicago in 2011–2012, suggesting that it was spreading from Hispanic to African American populations. The study stops there, but we can continue: in 2014 and 2015, “af” started appearing in BuzzFeed headlines, a decent measure of when it came to be co-opted by mainstream brands capitalizing on its association with African American coolness.
We’re especially likely to pick up new words when we’re first entering a community. Linguist Dan Jurafsky and his colleagues looked at over