The keyword term "patriot day national holiday" functions as a noun phrase. In this construction, the central element, or head noun, is "holiday." The other words in the phrase serve to modify and specify this core noun.
A grammatical analysis of the phrase reveals its components. "Holiday" is the head noun, establishing the concept as a specific day or period of observance. The word "national" is an adjective that modifies "holiday," indicating its scope and level of recognition. The term "Patriot Day" is a proper noun that acts as a noun adjunct (or adjectival noun). In this role, it further modifies "holiday" by providing its specific name, distinguishing it from other national holidays.
Understanding this term as a noun phrase is essential because it defines the entire concept as a specific entity. This classification allows the term to be used as a subject, object, or complement within a sentence, referring to the commemorative event itself. The structure clarifies that the article's focus is on a particular thinga named day of observancerather than an action or a simple description.