Definition & Meaning of "closed-class word"

What is a "closed-class word"?

A closed-class word is a word that belongs to a grammatical category with a limited and fixed number of members. These words typically include function words such as prepositions, conjunctions, pronouns, and articles. Examples of closed-class words are "and," "but," "in," "the," and "she." Unlike open-class words, which can easily accept new additions, like nouns and verbs, closed-class words do not change or expand frequently. Understanding closed-class words is important for analyzing sentence structure and the grammatical relationships between words, as they play a crucial role in connecting ideas and providing context within sentences.