Frontier
Frontier adjective - Located at or near a border.
Usage example: a frontier town with a reputation for vice and lawlessness
Nearby Word: frontiersman
Internal
Internal adjective - Situated farther in.
Both words in one sentence
- Their entire eastern frontier was also no longer covered by two huge empires that could keep it in check and replaced by several smaller, weaker states with their own internal and external feuds.
Source: Won the War, Lost the Peace - Tech Infantry has the Frontier Worlds Territory and a few other colony-world minor political entities who broke off from the Earth Federation, along with the various internal rebel groups who aren't so much interested in independence as in taking over the whole shebang for themselves.
Source: The War of Earthly Aggression
Cite this Source
Internal and Frontier. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/frontier/internal
Frontier & Internal. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/frontier/internal>.
Internal or Frontier. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/frontier/internal.
Google Ngram Viewer shows how "frontier" and "internal" have occurred on timeline