What is the definition of a pronoun?

A pronoun is a word that stands in for a noun. Like nouns, pronouns refer to people, things, concepts, or places. Most sentences contain at least one noun or pronoun.

A pronoun can serve as the subject or object in a sentence, and it will usually refer back (or sometimes forward) to an antecedent—the noun that the pronoun stands in for. Pronouns are used to avoid the need to repeat the same nouns over and over.