relative pronoun

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A pronoun that introduces a relative clause and has reference to an antecedent, as who in the child who is wearing a hat or that in the house that you live in.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun grammar A pronoun that introduces a relative clause and refers to an antecedent. Some words that can be used as interrogative pronouns can alternatively be used as relative pronouns: what, which, who, whom, and whose. The other relative pronouns are whoever, whosoever, whomever, whatever, and that.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a pronoun (as `that' or `which' or `who') that introduces a relative clause referring to some antecedent