The keyword term "wednesday/september 11th" functions grammatically as a proper noun. It operates as a single, indivisible unit that names a specific and unique point in time, much like a name for a person, place, or specific event.
This classification is determined by its syntactic function within a sentence. Both "Wednesday" and "September 11th" are individually proper nouns. The slash conjoins them into a compound nominal phrase that can act as the subject (e.g., "Wednesday/September 11th marks a solemn anniversary"), the object of a preposition (e.g., "The discussion centered on Wednesday/September 11th"), or a predicate nominative. While the phrase answers the adverbial question "when," its core grammatical category is that of a noun, allowing it to exist as the main subject of a clause rather than just a modifier.
Understanding this term as a proper noun is crucial for establishing it as the article's main point. This grammatical status allows the specific date itself to be the primary subject of analysis and discussion. It is not an adjective describing something else, nor a verb indicating an action, but the distinct entity being examined.
