Perhaps you first saw the phrase on Twitter.

Perhaps it was in a Washington Post or an Atlantic headline.

Since the election of President Donald Trump, the phrase "the resistance" has often been employed to reference the various groups that oppose - and hope to in some way disrupt - Trump's presidency. Mostly, it's been used as a social media hashtag, though there is a blog titled "The DJT Resistance" with an accompanying (and more frequently updated) Facebook page.

Now, documentarian and political commenter Michael Moore has launched a website titled "The Resistance Calendar," which allows anyone to post, as Moore phrased it, about "anti-Trump, pro-democracy" events in the United States.

Moore tweeted: "A few minutes ago, I launched RESISTANCE CALENDAR! A one-stop site for all anti-Trump actions EVERY DAY nationwide: https://t.co/c0W7beDdzF

In a lengthy Facebook post, Moore called the website a "place where you can quickly go and check it daily, ensuring that you don't miss any event in your area to stop the Trump madness."

It boasts a simple design - the main page is simply a list of events. Another page includes a form allowing users to post their own events, and a third includes a contact from. As of now, there are no other pages, though Moore promised upcoming features, such as a "killer map of the U.S. and a big desk-style calendar where you can just click on any day and see what's happening with the movement across America."

With the creation of the website, Moore seems bent on formalising the phrase that's been bubbling up since Trump announced his candidacy: The Resistance. As Moore wrote, it's become a political movement. But it's far from the first movement to use to the phrase as a moniker.

It was popularised as a political term during World War II, via France's La Résistance .

Nazis poured into Paris in June 1940, fulfilling the worst fears of many French residents - a German occupation. In an effort to invigorate the dispirited countrymen, general and leader of "Free France" Charles de Gaulle gave speeches on the BBC, encouraging the French to continue fighting in whatever way they could.

In one, he said, "I ask you to believe me when I say the cause of France is not lost . . . Whatever happens, the flame of French resistance must not and shall not die."

With these words, as noted in the New York Times, de Gaulle began establishing La Résistance, a collection of disparate groups united only by their desire to fight for an unoccupied France. They published underground newspapers, kept safe houses and engaged in guerrilla warfare practices against their occupiers. These acts often had dire consequences.

As Charles Kaiser wrote for CNN: "The French Resistance undertook nearly 1,000 acts of sabotage in the hours after the Normandy invasion began, and the damage they inflicted on railroads and other communications played a crucial role in preventing German reinforcements from arriving quickly in Northern France. And every time a German troop train was sabotaged, a nearby French village was likely to suffer horrendous retaliation - like the town of Tulle, where a hundred men where seized at random and massacred three days after the Normandy invasion, or the village of Oradour-sur-Glane, where 642 citizens, including 205 children, were killed the day after that. The men were shot; the women and children were burned to death in a church."

In May 1943, the groups were united under the National Council of Resistance.

According to Simon Adams' "Occupation and Resistance," "by 1944, the resistance had grown in strength to about 400,000 members."

Other resistance movements throughout Europe began to appear, and the usage of "resistance" to refer to such a group stuck - even today. In a 2014 joint publication, the U.S. Department of Defense defined a "resistance movement" as "An organised effort by some portion of the civil population of a country to resist the legally established government or an occupying power and to disrupt civil order and stability." The Oxford English Dictionary, meanwhile, defines "the resistance" as "The underground movement formed in France during the Second World War to fight the German occupying forces and the Vichy government."

The controversial orders Donald Trump has already issued Show all 9 1 /9 The controversial orders Donald Trump has already issued The controversial orders Donald Trump has already issued Trump and the media White House Press Secretary Sean Spicer takes questions during the daily press briefing Getty Images The controversial orders Donald Trump has already issued Trump and the Trans-Pacific Partnership Union leaders applaud US President Donald Trump for signing an executive order withdrawing the US from the Trans-Pacific Partnership negotiations during a meeting in the Roosevelt Room of the White House in Washington DC. Mr Trump issued a presidential memorandum in January announcing that the US would withdraw from the trade deal Getty The controversial orders Donald Trump has already issued Trump and the Mexico wall A US Border Patrol vehicle sits waiting for illegal immigrants at a fence opening near the US-Mexico border near McAllen, Texas. The number of incoming immigrants has surged ahead of the upcoming Presidential inauguration of Donald Trump, who has pledged to build a wall along the US-Mexico border. A signature campaign promise, Mr Trump outlined his intention to build a border wall on the US-Mexico border days after taking office Getty Images The controversial orders Donald Trump has already issued Trump and abortion US President Donald Trump signs an executive order as Chief of Staff Reince Priebus looks on in the Oval Office of the White House. Mr Trump reinstated a ban on American financial aide being granted to non-governmental organizations that provide abortion counseling, provide abortion referrals, or advocate for abortion access outside of the United States Getty Images The controversial orders Donald Trump has already issued Trump and the Dakota Access pipeline Opponents of the Keystone XL and Dakota Access pipelines hold a rally as they protest US President Donald Trump's executive orders advancing their construction, at Columbus Circle in New York. US President Donald Trump signed executive orders reviving the construction of two controversial oil pipelines, but said the projects would be subject to renegotiation Getty Images The controversial orders Donald Trump has already issued Trump and 'Obamacare' Nancy Pelosi who is the minority leader of the House of Representatives speaks beside House Democrats at an event to protect the Affordable Care Act in Los Angeles, California. US President Donald Trump's effort to make good on his campaign promise to repeal and replace the healthcare law failed when Republicans failed to get enough votes. Mr Trump has promised to revisit the matter Getty Images The controversial orders Donald Trump has already issued Donald Trump and 'sanctuary cities' US President Donald Trump signed an executive order in January threatening to pull funding for so-called "sanctuary cities" if they do not comply with federal immigration law AP The controversial orders Donald Trump has already issued Trump and the travel ban US President Donald Trump has attempted twice to restrict travel into the United States from several predominantly Muslim countries. The first attempt, in February, was met with swift opposition from protesters who flocked to airports around the country. That travel ban was later blocked by the Ninth Circuit Court of Appeals. The second ban was blocked by a federal judge a day before it was scheduled to be implemented in mid-March SANDY HUFFAKER/AFP/Getty Images The controversial orders Donald Trump has already issued Trump and climate change US President Donald Trump sought to dismantle several of his predecessor's actions on climate change in March. His order instructed the Environmental Protection Agency to reevaluate the Clean Power Plan, which would cap power plant emissions Shannon Stapleton/Reuters

While the phrase is often used in reference to President Trump without explicit allusion to La Résistance, some have drawn the comparison. Some publications, such as Wired, employ the phrase when discussing anti-Trump movements. Others, though, are more straightforward.

Days after Trump's election, Jennifer Boyer-Switala explained the La Résistance and wrote in the Huffington Post: "In light of our recent election, I look to General de Gaulle's Speech of 18 June 1940 when I ask you to join me in lighting the flame of resistance. Let me be clear; I am not calling for, nor do I condone, violent or armed resistance, as it only serves to harm fellow human beings and validate claims that we are hypocrites. Nor am I calling for a coup d'état. On the contrary: I am calling for a coup de paix. My appeal is for Americans to engage in peaceful acts of resistance as a means of effecting positive change."

Meanwhile interest in the La Résistance has certainly grown since the election. Google searches for the "French resistance" spiked on Inauguration Day, according to Google's search trends

Moore seems to hope his new website will continue to stoke interest in political resistance.

He wrote he hopes the calendar will become "a 24/7 clearinghouse of the already MASSIVE resistance to Trump, to the Republican Congress, and, yes, to many of the spineless Democratic politicians out there, before concluding, "Our goal is his removal from office - and the defeat of any politician who isn't with us. WE ARE THE MAJORITY."