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extragalactic

[ek-struh-guh-lak-tik]
adjective
  1. outside the Milky Way system.

Origin of extragalactic

First recorded in 1850–55; extra- + galactic
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for extragalactic

extragalactic

adjective
  1. occurring or existing beyond the Galaxy
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