The term is a noun phrase, where "zodiac" (a common misspelling of "zodiac") is the head noun. The component "September 11" is a compound noun functioning as an adjectival modifier. Therefore, the part of speech for the main point or subject of the phrase is a noun, as it refers to a specific thing: the astrological sign associated with a particular date.
In grammatical analysis, the word "zodiac" is a noun that refers to a conceptual system of astrological signs. When preceded by a date like "September 11," the date acts as a noun adjunct, which is a noun used to modify another noun. This construction specifies which particular zodiac sign is being referenced. For the date September 11, the corresponding sign in Western astrology is Virgo. Thus, the phrase is a specific identifier for the proper noun "Virgo" in this context.
For the purpose of an article, treating the keyword as a noun is essential. It allows the phrase to function as the subject of a sentence (e.g., "The September 11 zodiac is Virgo."), an object, or the topic of discussion. The core concept is an identity or classificationa specific astrological signwhich is fundamentally a noun. This understanding dictates that the article will be descriptive and informational, explaining the attributes of that particular zodiac sign.
