Joshua Lott via Getty Images A demonstrator holds a sign reading "No Human Is Illegal" during a protest in Chicago in June against Immigration and Customs Enforcement (ICE) and the Trump administration's immigration policies.

What comes to mind when we hear the word “illegal”?

A petty crime ― shoplifting perhaps? Something more horrific like murder? Tax fraud? Money laundering?

Most words have a commonly understood definition, but “illegal” is different. For many of us, questions as to what’s legal or not contain complex meanings that go far beyond what our laws actually state. We make judgments on what should or should not be legal, and on how bad some illegal acts are in relation to others. We grade them. We sort them. And we refer to these categorizations to make further judgments.

One of the clearest examples of this is found in the debate over undocumented immigration ― or, as it’s commonly referred to, “illegal” immigration. The topic has been part of our national conversation for decades. Most recently, the death of Mollie Tibbetts, along with damning reports that President Donald Trump’s Immigration and Customs Enforcement detained a record number of children (many of whom were separated from their parents), ensured that the subject commanded much of this summer’s news cycle.

“Illegal” is a simple word with a supposedly simple meaning that has, as words often do, become so laden with undefined meaning that different people think very different things when they use or hear it. How did a word with a very concrete definition become so politically charged?

Kevin Lamarque / Reuters President Donald Trump speaks during a tour of U.S.-Mexico border wall prototypes near the Otay Mesa Port of Entry in San Diego, California, on March 13, 2018.

Like 30 to 50 percent of English words, ”illegal” comes from a French word (from Latin) that was first used in English in the 1630s. At that time, it meant exactly what many people believe it still means today: something not permitted by law.

But things get murkier when the word is used to describe specific actions or people. The Naturalization Act of 1790 (America’s first immigration law) used the term “aliens” to refer to the “free white” people who were allowed to immigrate to this new country. It then, along with subsequent laws, delineated what made such an alien “illegal.” That term ― “illegal alien” ― still somehow remains the one officially recognized by the Justice Department.

The similarly slur-tinged term “illegal immigrant” has been in use since at least 1892, when it was (fittingly) used in Congress in a discussion about immigrants taking American jobs (though the argument focused on punishing business owners who took advantage of existing laws and called racial prejudice unpatriotic, making it more advanced than the views of many people today).

“Illegal immigrant” wasn’t used in major newspapers until the 1930s, when it appeared in a handful of news stories and government reports. It gained traction from there, becoming more and more common until taking off in the late 1960s and early 1970s in the aftermath of the Immigration and Nationality Act, and continues to be widely used. It’s probably no coincidence that immigration started being widely described as illegal just after a law was passed that allowed more people from Latin America, Africa and Asia to come to the United States.

When the word “illegal” is used in connection with immigration, it instantly receives a much different meaning than originally intended. Using the word to describe a human being (rather than an action) has, rightly, fallen out of favor with immigration activists. While arguably better than using blatant racist slurs, the dehumanizing dog whistle that is describing a human being’s existence in a place ― in many cases where they’ve lived for years ― as “illegal” is obvious.

Bloomberg via Getty Images A demonstrator in Washington, D.C., holds a sign reading "No Human Is Illegal" while marching past the Trump International Hotel during a protest against the president's immigration policies.

And the fact that questioning a person’s immigration status has become weaponized, regardless of what their immigration status actually is, only adds strength to the idea that this word no longer serves to simply denote a legal status. Worse yet is the single word “illegals,” which many Americans, including our president, have adopted. It’s used by racists to describe a variety of people, the unifying theme being they are somehow different from the rest of us and not American.

Turning an adjective describing codified acts into a noun describing a class of people is a particularly hateful development in and of itself, but it’s impressively deployed in its purpose to describe certain people as less than human (or at least less than the right kind of human). It uses perceived criminality as an excuse for engaging in abuse, in line with the “bandits” of the Warsaw Ghetto, the “delinquents” of the Santa Cruz Massacre and the fictitious would-be saboteurs blamed for Japanese internment. And in case the comparisons weren’t already clear enough, the president, who ran a campaign on deportation and walls, has also likened immigrants to vermin and “animals.”

Mike Blake / Reuters U.S. Attorney General Jeff Sessions speaks during a press conference at the U.S.-Mexico border wall on May 7, 2018.

One might argue our current attitudes and actions haven’t yet risen to the level of the atrocities mentioned above. But this isn’t just a question of basic human dignity. It’s about our society taking those first dangerous steps down a path and not realizing it until it’s too late.

When a word is used to describe multitudes of people (individuals seeking asylum, immigrants dealing with simple paperwork issues, the hundreds of American citizens unlawfully detained and, lastly, some who may in fact be criminals) as if they are somehow not deserving of human consideration, the word becomes a label. And that label is used not to describe certain actions but to describe people. When that happens, the label then becomes a slur.

NurPhoto via Getty Images A demonstrator holds a sign reading "No Human Is Illegal" during a protest against President Trump's immigration policies in New York, New York on June 30, 2018.

Trace the word “illegal” back far enough, and you arrive at the Latin word lex, which means, among other things, “a principle.” Go farther back to Proto-Indo-European, an ancient forebear to hundreds of our world’s languages, and you arrive at leg, “to gather or collect.” Laws are meant to be a reflection of a society’s values. A collection of its principles. They aren’t meant to be blindly followed if they become unjust.

After many years and several presidential administrations, America’s immigration situation is teetering near a self-inflicted crisis point, and if our current laws enable (or promote) undue suffering and human rights abuses and atrocities, it might be time to rethink them.

Then, after a permanent end to this crisis is finally negotiated, one of the many things we’ll have to think hard about as a society is which actions we deem “illegal” in America ― and what that says about us as a country.

Brenden Layte is a linguist and an editor of educational materials for students learning English as a second language. He serves on the board of a nonprofit that provides free supplementary education to students in Mexico and Nicaragua.