pronoun

n. (Grammar) word used to replace nouns and noun phrases (she, we, this, etc.)

In linguistics and grammar, a pronoun is a pro-form that substitutes for a noun or noun phrase with or without a determiner, such as and in English. The replaced phrase is the antecedent of the pronoun. A pronoun used for the item questioned in a question is called an interrogative pronoun, such as .
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(n.)
A word used instead of a noun or name, to avoid the repetition of it. The personal pronouns in English are I, thou or you, he, she, it, we, ye, and they.
  

Noun
1. a function word that is used in place of a noun or noun phrase
(hypernym) function word, closed-class word
(hyponym) anaphoric pronoun