The keyword term "patriot day heroes" functions as a noun phrase. Within this phrase, the primary grammatical component and the main point is the word "heroes," which is a noun.
Detailed analysis reveals that "heroes" serves as the head noun of the phrase. The preceding words, "Patriot Day," collectively act as a compound adjective modifying "heroes." Specifically, "Patriot" originates from a noun but functions adjectivally to describe "Day," forming the proper noun "Patriot Day." When "Patriot Day" is used before "heroes," it specifies the particular context or association of these heroes, thus taking on an attributive (adjectival) role, describing which heroes are being referred to. Therefore, the entire construction specifies a particular group of individuals (heroes) linked to a specific event or observance (Patriot Day).
Consequently, while composed of elements that include nouns acting adjectivally, the overarching grammatical classification for the keyword "patriot day heroes" is a noun phrase, with its central part of speech being a noun.
