Also found in: Thesaurus.
1. Impossible to overcome or overthrow by force.
2. Impossible to put aside or drive away: inexpugnable dislike.
[Middle English, from Old French, from Latin inexpugnābilis : in-, not; see in-1 + expugnābilis, capable of being overcome (from expugnāre : ex-, completely; see ex- + pugnāre, to fight; see impugn).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.