Function word

 Function words are words that don't have an independent lexical meaning; they don't name things, actions, or qualities. Instead, their role is to connect and organize content words (nouns, verbs, adjectives, etc.) within a sentence. They show the grammatical relationships between words and give structure to the sentence. Examples include prepositions, conjunctions, articles, pronouns, and auxiliary verbs.

Examples:

1. Preposition: "The book is *on* the table."  (on shows the location of the book)

2. Conjunction: "I bought apples *and* pears." (and joins two elements of the sentence)