Don’t deny it: Sometimes, swearing just feels good. And it’s becoming increasingly clear that dropping the occasionally profanity bomb is actually good for us, too — at least, according to science.

Research has shown that swearing can boost pain tolerance, foster emotional resilience and signal positive traits like verbal fluency and honesty. What’s more, spewing obscenities has the potential to impact our bodies as well as our minds, providing stress relief and even a slight boost in physical performance.

Given their ubiquity in society, it can seem like swear words simply sprouted into existence. But where, exactly, does profane language come from? From ancient Rome to the Renaissance to today, there’s lots that the history of swearing can teach us about how taboos, language and culture evolve — and it can provide a glimpse of the future of (mostly) four-letter words.

Curse Words

Simply put, swearing is taboo language: particular words that certain people deem unacceptable in specific settings within a given culture.

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“The words that come to fill that role come from certain places in the human experience,” says Benjamin Bergen, a linguist and cognitive scientist at the University of California, San Diego, and author of What the F: What Swearing Reveals About Our Language, Our Brains, and Ourselves. “They tend to describe things that are themselves taboo.”

Historically, Bergen continues, taboo language has tended to revolve around religion; in Judeo-Christian and Muslim traditions, profanity emerges when words selected for specific functions are stripped of their intent and used outside of religious contexts. (In Latin, the word profanus translates to “outside the temple,” signifying words that desecrate sacred precepts.) As such, words in English like holy, hell and goddamn — or even names of religious figures like Jesus Christ — become swears when they’re used accordingly, even if they’re pretty tame by today’s standards.

Beyond religion, profanity can also come from language involving sex and sexual acts, as well as bodily functions — in the latter category, you can find words describing vomit, urine and, of course, feces. In certain cultures, death and disease can even become fodder for profane language. In Dutch, for example, a long list of expletives are derived from the names of diseases, like the extremely-offensive Kankerlijer, which literally translates to “cancer-sufferer.”

“It’s the same general phenomenon [in all cases],” says Bergen. “A taboo about the world becomes a taboo about the word.”

Lastly, there are slurs — among the most offensive of all profanity, according to several studies that rank the offensiveness of English swear words. These derogatory terms refer to members of groups perceived as being defined by their race, gender, ethnicity and sexual orientation, among others. And, according to Bergen, the prominence of slurs in the U.S. is on the rise.

“There’s very clear, empirical evidence that not only is there more of [this type of language], but it’s also judged to be more offensive, at least by younger Americans,” he says.

Swear Words in Ancient Rome

The history of swearing is filled with fascinating twists and turns. But, perhaps surprisingly, obscenity in Latin shares a few striking similarities with swearing today, with both drawing from taboos about sex and excrement. The sexual and cultural norms of ancient Rome, however, were markedly different from ours, giving rise to some unique profanity.

“You get swear words from the cultural preoccupations of the time,” says Melissa Mohr, author of Holy Sh*t: A Brief History of Swearing. “One of the key Roman preoccupations was, ‘What does it mean to be a man?’ They had all of these different words for man, and the best kind of man you could be was a vir, and that’s where we get the word virtuous.”

In ancient Rome, Mohr continues, it was socially acceptable for a virtuous Roman man to have sex with people of any gender, for example, so long as he was the active participant. (As such, one of the surest ways to sling mud at a Roman man was to use language putting them in a passive sexual position.) Meanwhile, if a woman was active during sex, that was deemed taboo by society.

“When you transgress the rules, that’s where you get the swear words,” adds Mohr.

Swearing in the Middle Ages

By the Middle Ages, our cultural norms were quite different from those in antiquity; now, religion was an even more dominant force in society. As such, religious oaths — promises before God that your words are true and you’ll do what you say — that were made falsely became the predominant form of profanity.

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“The cultural preoccupation [in the Middle Ages] is how and when you use God’s name,” says Mohr. “If you were having a criminal trial, you could be found not guilty just because you swore that you were a good person. […] So when you get vain swearing, which is what they’re worried about, that’s when you swear and you’re lying or you’re not sincere.”

So if you were, say, gambling in the Middle Ages and lost, you might cry out, “By God’s bones!” In particular, oaths on God’s body parts — other examples include “by God’s wounds” or “by the blood of Christ” — were the most obscene phrases you could say. These swears were deemed so shocking because people thought that saying them was akin to ripping apart the body of Christ in heaven, in a perversion of the Eucharist here on Earth.

Over the centuries, however, the perverse power of religious oaths began to fade. Mohr says that the decline started during the Protestant Reformation of the 1500s, with traditional religion playing a less central role in people’s lives.

“Basically, in Catholicism, God is more reachable; there was a sense [during the Middle Ages] that swearing was really directly connected to God and that vain swearing was really bad when you did it,” she says. “And with the Protestant Reformation, it’s no longer God’s physical body; it’s his spiritual body. […] With the decline of religiosity, this has basically been on a downward trend for hundreds of years.”

Modern Obscenity Was Born During the Renaissance

During the Renaissance, swearing started to more closely resemble modern profanity. Terms that had simply been direct or descriptive during the Middle Ages — like the C-word, which could once be found in medical treatises describing anatomy — began to take over as the new swear words.

“Most of the bad words were around in the Middle Ages, they just weren’t swear words,” says Mohr.

These swears, often sexual or scatological in nature, reached their peak offensiveness during the Victorian era. This is when profanities largely vanished from print and speech, and polite euphemisms took their place. The societal urge to veer away from anything deemed uncouth or explicit was so strong that even now-banal words like leg and trouser were seen as taboo.

“But in private, there were all of these hints that by around 1860, people were swearing basically the same way that they are now,” says Mohr. “It just rarely made it into the record, but it’s in court cases and pornography.”

Around the dawn of the 20th century, however, profanity became much more public. During World War I and World War II, says Mohr, wartime correspondents tried to faithfully report on what soldiers were doing and saying, from trenches to submarines — including all of the colorful language they used. As a result, swearing started to bleed into newspapers and books.

“At that point, they’re saying f— every other word,” adds Mohr. “There’s a quote [from the era] where someone said, ‘We knew it was serious if the sergeant didn’t say, ‘Get your f—ing rifle.’”

What Will the Swear Words of the Future Look Like?

Today, slurs are increasingly replacing other forms of profanity as the most shocking and offensive words in the English language. And while research suggests that the bulk of profanity is mostly harmless, even when used around children, slurs are a notable exception to this rule — for both the individuals being defamed and observers.

For example, Italian researchers found that being exposed to homophobic slurs led participants to dehumanize and physically distance themselves from gay men, according to a study published in the European Journal of Social Psychology.

As slurs become more pervasive, both Bergen and Mohr note that it’s difficult to say whether they’ll ever lose their intent to harm and become intensifiers in language like other forms of swearing.

“One way to look at it is to say that, in hundreds of years, when we stop being discriminatory and putting people in all these silos, maybe [slurs] will just be this remnant of a time when this mattered,” says Mohr. “I hope that’s going to go away, but I feel like maybe they’ll never become the ‘seasoning’ words of the future.”

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