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polytene

British  
/ ˈpɒlɪˌtiːn /

adjective

  1. denoting a type of giant-size chromosome consisting of many replicated genes in parallel, found esp in Drosophila larvae

"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 polytene

C20: from poly- + Greek taenia band