Is it Presidents Day, President's Day, or Presidents' Day? This might just be the greatest question of our time.

And unfortunately, nobody has the slightest clue. If they claim to know the right answer, they're lying.

Presidents Day has been an extremely confusing holiday ever since George Washington died in 1799 and people decided we ought to figure out a way to celebrate the guy. Complicating matters was that when George Washington was born in 1731 (or 1732 — like I said, it's confusing), North America still used the Julian calendar, which was 11 days behind the Gregorian calendar. During Washington's lifetime, North America switched to using the Gregorian calendar, which technically changed Washington's birthday from Feb. 11 to Feb. 22. For years after the cherry tree murderer's death,"Washington's Birthday" was celebrated on his new birthday, Feb. 22.

A few centuries later, in 1968, Congress decided it'd be better if Americans had more three-day weekends (agree), and they issued the Uniform Monday Holiday Act, which officially moved George Washington's birthday to "the third Monday in February." Which was all fine and good, except that it prevented Washington's birthday from ever being celebrated on Washington's actual birthday (by being the third Monday of the month, the holiday can only ever fall between Feb. 15 and Feb. 21).

Anyway, while Congress was busy figuring out the whole three-day weekend thing in 1968, some people had the bright idea of renaming the holiday "Presidents' Day," which would have saved us all a lot of trouble by officially designating that the apostrophe belongs at the end of the ascriptive noun. Alas, it was decided that "not all Presidents are held in the same high esteem as the Father of our Country" and the holiday was signed into law as "Washington's Birthday," as it is still federally known. Presidents Day, and all its variations, emerged as the favored colloquialism, in part to more broadly honor the office of the presidency and in part because celebrating "Washington's Birthday" on a different day each year is just silly.

The problem was, with no official standard to prevent them from doing otherwise, state governments, advertisers, your aunt on Facebook, schoolchildren, professors, and stressed-out web journalists have begun to wantonly stick the Presidents Day apostrophe anywhere they darn please. Or nowhere! And it has been grammatical chaos ever since.

Take, for example, that it's officially "Presidents' Day" in Hawaii, "President's Day" in Wyoming, and "Presidents Day" in New Jersey. Meanwhile, it's "George Washington Day" in Virginia, "Washington's Birthday" in New York, and "Washington's and Lincoln's Birthday" in Minnesota (Colorado, meanwhile, went for the hyphen with "Washington-Lincoln Day"). Alabama throws in Thomas Jefferson's birthday for good measure, and in Arkansas it's "George Washington's Birthday and Daisy Gatson Bates Day," which is really a mouthful if you ask me.

But that's just getting started. Amazon has "Presidents' Day savings on bedding," Sur La Table is offering up to 70 percent off in their "President's Day sale," and Sears is celebrating the three-day weekend with a "Presidents Day Event." In Littleton, Massachusetts, the Acton Toyota invites you to their "Washington's Birthday Sales Event." The AP Stylebook will ask that you use "Presidents Day" and Chicago Style prefers "Presidents' Day." The Obama White House fluctuated recklessly between Presidents' and President's, while President Trump appears to have aligned with Team Presidents.

There are other grammatically confusing holidays, but unlike Presidents Day, they all actually have a correct style: It's New Year's Eve, Mother's Day, and Martin Luther King Jr. Day (no matter what The New Yorker tries to claim otherwise with its commas). But without federal guidance on where to place the dang possessive apostrophe in Presidents, we are left adrift.

What's particularly distressing is that depending on which variation of Presidents you choose, you change the entire meaning of the holiday. Presidents Day makes it a plural holiday that democratically honors everyone that has ever been an American president, from George Washington to Zachary Taylor to Lyndon B. Johnson to Mr. 45. It is celebrating the whole concept of presidents, the way "Horses Day" would celebrate horses or "Spaghetti Day" would require you to reflect on the merits of cylindrical pastas.

Presidents' Day is a slight but important variation. With the apostrophe after the plural base "presidents," this suggests the day belongs to all of the presidents individually: It is George Washington's Day and Andrew Jackson's Day and Barack Obama's Day. President's Day, on the other hand, is a singular possessive and proposes the day belongs to just one president; depending on your interpretation, that could be George Washington or Herbert Hoover or the president in office. Personally, whenever I see President's Day stylized like this, I like to pretend it's exclusively in honor of Millard Fillmore.

Alas, we can only be sure of one thing, which is that it is definitely not President's' Day. Although frankly, at this point, maybe it should be.