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xerarch

American  
[zeer-ahrk] / ˈzɪər ɑrk /

adjective

Ecology.
  1. (of a sere) originating in a dry habitat.


xerarch British  
/ ˈzɪərɑːk /

adjective

  1. ecology (of a sere) having its origin in a dry habitat

"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 xerarch

1935–40; xer- ( def. ) + -arch