In 2016, I was offered a promo code to test out a new app designed to help young people talk without filler phrases like you know and like, so they could sound more “authoritative.” I tried not to take the offer personally. For decades, like has been a subject of deep linguistic ridicule — along with vocal fry and uptalk, it is probably the most recognizable aspect of “Valley girl speak.” When making fun of teenage girls, imitators go for these sorts of phrases: “I, like, went to the movies? And I was like, ‘I want to see Superwoman?’ But Brad was like, ‘No way?’ So we, like, left.” (I’m not certain why people love satirizing teen girls so much, but my theory is that it’s just an excuse to speak in this highly entertaining fashion.)

Fortunately, there are plenty of language experts who’ve taken “Valley girl” speak seriously enough to figure out what it actually is. One of these scholars is Carmen Fought, a linguist from Pitzer College, who says, “If women do something like uptalk or vocal fry, it’s immediately interpreted as insecure, emotional or even stupid.” But the truth is much more interesting: Young women use the linguistic features that they do, not as mindless affectations, but as power tools for establishing and strengthening relationships. Vocal fry, uptalk and even like, are in fact not signs of ditziness, but instead all have a unique history and special social utility. And women are not the only people who use them.

Despite the word’s detractors, like is in fact extremely useful and versatile. Alexandra D’Arcy, Canadian linguist at the University of Victoria, has dedicated much of her research to identifying and understanding the many functions of like. D’Arcy ebulliently describes her work for the university’s YouTube channel: “Like is a little word that we really, really don’t like at all — and we want to blame young girls, who we think are destroying the language,” she explains. But the truth is that like has been a part of English for more than 200 years. “We can find speakers today in their 70s, 80s and 90s around little villages in the United Kingdom, for example,” D’Arcy says with a smile, “who use like in many of the same ways that young girls today are using it.”

According to D’Arcy, there are six completely distinct forms of the word like. The two oldest types in English are the adjective like and the verb like. In the sentence, “I like your suit, it makes you look like James Bond,” the first like is a verb and the second is an adjective — and even the crabbiest English speakers are fine with both. Today, these two likes sound exactly the same, so most people don’t even notice that they’re different words with separate histories. They’re homonyms, just how the noun watch (meaning the timepiece on your wrist) and the verb watch (meaning what you do with your eyes when you turn on the TV) are homonyms. The Oxford English Dictionary says that the verb like comes from the Old English term lician, and the adjective comes from the Old English līch. The two converged at some point over the last 800 or so years, giving us lots of time to get used to them.

But four new likes developed much more recently than that — and D’Arcy says these are all separate words with distinct uses, as well. Only two of these likes are used more frequently by women, and only one of them is thought to have been masterminded by young Southern California females in the 1990s. That one would be the quotative like, which you hear in, “I was like, ‘I want to see Superwoman.’” As lampooned as it is, pragmatically speaking, this like is one of my favorites because it allows you to tell a story, to relay something that happened, without having to quote the interaction verbatim. For example, in the sentence “My boss was like, ‘I need those papers by Monday,’ and I was like, ‘Are you f—ing kidding me?’” you’re not repeating what you truly said but instead using like to convey what you wanted to say or how you felt in the interaction. Thanks, Valley girls. This very useful quotative like continues to explode in common usage.

The other like that women tend to use more frequently is categorized as a discourse marker and can be found in contexts such as, “Like, this suit isn’t even new.” A discourse marker — sometimes called a filler word — is a type of phrase that can help a person connect, organize or express a certain attitude with their speech. Other discourse markers include the hedges just, you know and actually.

There are two last forms of like: one is an adverb, which is used to approximate something, as in the sentence, “I bought this suit like five years ago.” As of the 1970s this like has largely replaced the approximate adverb about in casual conversation, and it has always been used equally among men and women (so it isn’t hated as much). And last, there’s the discourse particle like, which we hear in, “I think this suit is like my favorite possession.” This like is similar to the discourse marker, except that it’s not used in quite the same way syntactically or semantically; plus, dudes use it just as much as women do (D’Arcy doesn’t know quite why that is), though they’re almost never ridiculed for it.

Objectively, we can see that using one, two or all of these different likes in the same sentence isn’t inherently bad. As a matter of fact, some studies have demonstrated that speech lacking in likes and you knows can sound too careful, robotic or unfriendly. So next time someone accuses you of saying like too much, feel free to ask them, “Oh really? Which kind?” Because D’Arcy says that ordinary speakers tend to buy into the Valley girl stereotype so hardcore, blaming young women for all of these likes, simply because they don’t notice the differences among them.

From the book WORDSLUT. Copyright © 2019 by Amanda Montell. Published on May 28, 2019 by Harper Wave, an imprint of HarperCollins Publishers. Reprinted by permission.

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