The terms "Patriots' Day" and "Patriot Day" function as distinct proper nouns, each naming a separate and unrelated observance. The core distinction is both grammatical and historical. "Patriots' Day," with an apostrophe 's', is a state holiday in April celebrating the first battles of the American Revolutionary War. In contrast, "Patriot Day," without an apostrophe, is the national day of remembrance on September 11, honoring the victims of the 2001 terrorist attacks.
Patriots' Day is officially observed on the third Monday in April in Massachusetts and Maine. It commemorates the Battles of Lexington and Concord, which occurred on April 19, 1775, marking the start of the American War of Independence. This holiday is famously associated with events like the Boston Marathon and historical reenactments. Patriot Day, on the other hand, is a national observance held annually on September 11. Proclaimed in 2001, it serves as a Day of Service and Remembrance for the nearly 3,000 individuals killed in the attacks on the World Trade Center, the Pentagon, and in Shanksville, Pennsylvania. Observances include flying the American flag at half-staff and a national moment of silence.
The practical application of this distinction is crucial for historical and cultural accuracy. Using the correct name ensures clear communication and honors the appropriate event and its associated significance. The presence of the apostrophe in "Patriots' Day" signifies a commemoration of multiple historical patriots of the Revolutionary era, whereas the singular "Patriot Day" refers to a unified, modern spirit of patriotism in response to a national tragedy. Therefore, the choice of term is not a matter of style but of factual correctness, directly tied to the specific history being referenced.