Why is it mother's day and not mothers' day It is a day for mothers throughout It's plural right?

Mother's Day is named to honor and celebrate a singular concept of motherhood, emphasizing the role of mothers as a collective. The apostrophe before the "s" indicates that the day belongs to mothers, rather than suggesting it is a day for multiple mothers. While it acknowledges all mothers, the focus is on the idea of motherhood itself, making "Mother's Day" the more widely accepted term.