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tristichous

American  
[tris-ti-kuhs] / ˈtrɪs tɪ kəs /

adjective

  1. arranged in three rows.

  2. Botany. arranged in or characterized by three vertical rows.


tristichous British  
/ ˈtrɪstɪkəs /

adjective

  1. arranged in three rows, esp (of plants) having three vertical rows of leaves

"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 tristichous

First recorded in 1855–60, tristichous is from the Greek word trístichos of three rows or verses. See tri-, -stichous