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aza-

British  

combining form

  1. denoting the presence of nitrogen, esp a nitrogen atom in place of a -CH group or an -NH group in place of a -CH 2 group

    azathioprine

"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 aza-

C20: from az ( o ) - + -a-