subordinate clause

noun Grammar.
  1. a clause that modifies the principal clause or some part of it or that serves a noun function in the principal clause, as when she arrived in the sentence I was there when she arrived or that she has arrived in the sentence I doubt that she has arrived.
Compare main clause.
Also called de·pend·ent clause.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for subordinate clause

subordinate clause

noun
  1. grammar a clause with an adjectival, adverbial, or nominal function, rather than one that functions as a separate sentence in its own rightCompare coordinate clause, main clause
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