Today is officially Mother’s Day, and as with other holidays with possessive or plural endings, there’s a lot of confusion about what the correct form of the name is. The creator of Mother’s Day in the United States, Anna Jarvis, specifically stated that it should be a singular possessive to focus on individual mothers rather than mothers in general. But as sociolinguist Matt Gordon noted on Twitter, “that logic is quite peccable”; though it’s a nice sentiment, it’s grammatical nonsense.
English has a singular possessive and a plural possessive; it does not have a technically-plural-but-focusing-on-the-singular possessive. Though Jarvis may have wanted everyone to focus on their respective mothers, the fact is that it still celebrates all mothers. If I told you that tomorrow was Jonathon’s Day, you’d assume that it’s my day, not that it’s the day for all Jonathons but that they happen to be celebrating separately. That’s simply not how grammatical number works in English. If you have more than one thing, it’s plural, even if you’re considering those things individually.
This isn’t the only holiday that employs some grammatically suspect reasoning in its official spelling—Veterans Day officially has no apostrophe because the day doesn’t technically belong to veterans. But this is silly—apostrophes are used for lots of things beyond simple ownership.
It could be worse, though. The US Board on Geographic Names discourages possessives altogether, though it allows the possessive s without an apostrophe. The peak named for Pike is Pikes Peak, which is worse than grammatical nonsense—it’s an officially enshrined error. The worst part is that there isn’t even a reason given for this policy, though presumably it’s because they don’t want to indicate private ownership of geographical features. (Again, the apostrophe doesn’t necessarily show ownership.) But in this case you can’t even argue that Pike is a plural attributive noun, because there’s only one Pike who named the peak.
The sad truth is that the people in charge of deciding where or whether to put apostrophes in things don’t always have the best grasp of grammar, and they don’t always think to consult someone who does. But even if the grammar of Mother’s Day makes me roll my eyes, I can still appreciate the sentiment. In the end, arguing about the placement of an apostrophe is a quibble. What matters most is what the day really means. And this day is for you, Mom.