The keyword phrase "september 11th element" functions as a noun phrase. The primary part of speech, which serves as the main point or headword of the phrase, is the noun "element."
In this construction, "september 11th" acts as an adjectival modifier, specifying which particular "element" is being discussed. It is a compound modifier derived from a proper noun (the date) that describes the noun that follows it. Grammatically, "element" is the head of the phrase, and "september 11th" is the dependent modifier. Therefore, the entire unit should be treated as a single noun that names a specific concept, component, or factor.
For the purpose of analysis within an article, identifying the core term as a noun is crucial. This establishes the phrase as a subject, object, or concept to be defined, analyzed, or discussed. The phrase refers to a specific entity or abstract idea directly linked to the events of September 11th, similar to how one might analyze terms like "economic factor" or "historical component."
