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extraposition

American  
[ek-struh-puh-zish-uhn] / ˌɛk strə pəˈzɪʃ ən /

noun

Linguistics.
  1. a rule of transformational grammar that shifts a subordinate or modifying clause to the end of a sentence, as in changing That you sign the paper is necessary to It is necessary that you sign the paper.


extraposition British  
/ ˌɛkstrəpəˈzɪʃən /

noun

  1. placement of something outside something else

  2. transformational grammar a rule that moves embedded clauses out to the end of the main clause, converting, for example, A man who will help has just arrived into A man has just arrived who will help

"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 extraposition

1925–30; extra- + position; apparently coined by Otto Jespersen