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subordinating conjunction

American  
Or subordinate conjunction

noun

Grammar.
  1. a conjunction introducing a subordinate clause, as when in They were glad when I finished.


subordinating conjunction British  

noun

  1. a conjunction that introduces subordinate clauses, such as if, because, although, and until Compare coordinating conjunction

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of subordinating conjunction

First recorded in 1870–75; subordinate + -ing 2

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

While or any other subordinating conjunction introduces a dependent clause; a dependent clause is not a sentence; it can never stand alone.

From English: Composition and Literature by Webster, W. F. (William Franklin)