The keyword term functions as a compound noun phrase. Within this structure, "Monday" is the head noun, which is modified by the preceding noun "holiday" acting as a noun adjunct. The subsequent noun phrase "September 11" serves as an appositive, further specifying the exact date of the Monday being referenced. The entire phrase collectively names a single, specific conceptual entity: a particular day.
A detailed grammatical analysis shows a clear syntactic hierarchy. The term "holiday" operates as a noun adjunct, a noun used adjectivally to describe the type of day, similar to its function in phrases like "holiday season" or "bank holiday." The core of the phrase is "Monday," the primary noun. This is immediately followed by "September 11," a noun phrase in apposition that renames and identifies the specific Monday in question. This relationship binds the individual words into a cohesive unit that refers to a singular subject.
Recognizing the term as a noun phrase is crucial for an article's focus, as it establishes the main point as an entity rather than an action (verb) or a quality (adjective). The article's purpose, therefore, would be to define, describe, analyze, or provide information about this specific date as a potential holiday. This grammatical classification dictates that the content should center on the existence, history, observance, or significance of the day itself, treating it as the central subject of discussion.
