[1] : The Collaborative International Dictionary of English v.0.48

darrein \dar"rein\, a. of. darrein, darrain, fr. an assumed ll.
   deretranus; l. de + retro back, backward. law
   last; as, darrein continuance, the last continuance.
   1913 webster

[2] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

darrein. a corruption of the french word "dernier," the last. it is 
sometimes used as, "darrein continuance," the last continuance. when any 
matter has arisen in discharge of the defendant in action, he may take 
advantage of it, provided he pleads itpuis darrein continuance; for if he 
neglect to do so, he waives his right. vide article darrein continuance. 

Darrein >> D Words
Darrein, definition of term: Darrein
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