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extravascular

American  
[ek-struh-vas-kyuh-ler] / ˌɛk strəˈvæs kyə lər /

adjective

Anatomy.
  1. situated outside a blood vessel or vessels.


extravascular British  
/ ˌɛkstrəˈvæskjʊlə /

adjective

  1. anatomy situated or occurring outside a lymph or blood vessel

"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 extravascular

First recorded in 1795–1805; extra- + vascular