relative clause

dependent clause, clause that modifies a word in the main clause (Grammar)

A relative clause is a subordinate clause that modifies a noun. For example, the noun phrase the man who wasn't there contains the noun man, which is modified by the relative clause who wasn't there. In many languages, relative clauses are introduced by a special class of pronouns called relative pronouns; in the previous example, who is a relative pronoun. In other languages, relative clauses may be marked in different ways: they may be introduced by a special class of conjunctions called relativizers; the main verb of the relative clause may appear in a special morphological variant; or a relative clause may be indicated by word order alone. In some languages, more than one of these mechanisms may be possible.
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Noun
1. a clause introduced by a relative pronoun; "`who visits frequently' is a relative clause in the sentence `John, who visits frequently, is ill'"
(hypernym) clause