The keyword phrase "what day is patriot day this year" is an interrogative clause. Its grammatical function is to request information that identifies a specific noun: the date of the observance. The main point or the core concept sought by this query is a proper noun (the date, September 11th). The interrogative pronoun "what" combined with the noun "day" specifies the type of information required, while the adverbial phrase "this year" contextualizes the query to the current calendar cycle. Therefore, the central purpose of the phrase is to identify a noun.
Patriot Day is observed annually in the United States on September 11th. This date is fixed by federal law (36 U.S.C. 144) and does not change from year to year. The day was established to commemorate the individuals who lost their lives in the terrorist attacks of September 11, 2001. The formal name is "Patriot Day and National Day of Service and Remembrance," and it serves as a day to remember the victims and to honor the first responders and individuals who rose in service following the attacks.
While the date for Patriot Day remains constant, the day of the week on which it is observed changes annually. In 2024, September 11 falls on a Wednesday. On this day, the President of the United States directs that American flags at all government buildings and establishments be flown at half-staff. It is also important to distinguish Patriot Day (September 11) from Patriots' Day, a state-level holiday in Massachusetts and Maine observed in April to commemorate the Battles of Lexington and Concord.