Every year on this date, I think perhaps I won’t be annoyed the next year with missing or errant apostrophes in the name of the holiday, that people will catch on to the correct punctuation. But how can they when they see rampant errors in advertising? (I do wonder whether the holiday exists primarily for Macy’s to have a sale on towels and bedding.)
Today I have seen PRESIDENTS DAY, PRESIDENT’S DAY and PRESIDENTS’ DAY. Which is it? This is simple. Obviously, the name is a possessive. Just decide how many presidents the day belongs to. If it were on Lincoln’s or Washington’s birthday, it would be PRESIDENT’S. But since the day is in memory of both Lincoln and Washington, the apostrophe goes after the final S: PRESIDENTS’.
When deciding where a possessive apostrophe needs to go, ask yourself whom the item belongs to. Think of the apostrophe as an arrow pointing to the owner word. Then add APOSTROPHE S. If the new word you’ve formed ends in two or three esses (weird word), just drop the final S. It’s not wrong to leave it, but the trend is toward eliminating it:
Three dogs’s tails——-> three dogs’ tails
My boss’s memos——–> my boss’ memos (pronounced “bosses,” which happens to be the plural of boss)