Relative pronoun - Wikipedia
https://en.wikipedia.org/wiki/Relative_pronounA Relative pronoun is a pronoun that marks a relative clause. It serves the purpose of conjoining modifying information about an antecedent referent. An example is the word which in the sentence "This is the house which Jack built." Here the relative pronoun which conjoins the relative clause "Jack built," which modifies the noun house in the main sentence. Which has an anaphoric relationship to its antecedent "house" in the main clau…