Synonyms of frontier

frontier 1 of 2

noun

ˌfrən-ˈtir 

1

as in border

a region along the dividing line between two countries

the Apaches were once feared on both sides of the U.S.-Mexico frontier

Synonyms & Similar Words

• border
• borderland
• march
• no-man's-land

2

as in countryside

a rural region that forms the edge of the settled or developed part of a country

Alaska has been called America's last frontier

Synonyms & Similar Words

• countryside
• country
• backwater
• backwoods
• hinterland
• backcountry
• bush
• outback
• up-country
• (the) back of beyond
• outlands
• backland(s)
• boondocks
• boonies
• sticks

frontier

2 of 2

adjective

as in marginal

located at or near a border

a frontier town with a reputation for vice and lawlessness

Synonyms & Similar Words

• marginal
• outer
• outside
• borderline
• exterior
• external
• outermost
• outward
• outmost

Antonyms & Near Antonyms

• interior
• inner
• internal
• inside
• inward
• central
• middle
• innermost
• mid
• inmost

Example Sentences

Recent Examples of frontier

Noun

As frontier models become increasingly accessible, competitive advantage won't come from having access to AI. — Prajkta Waditwar, Forbes.com, 2 Sep. 2026

That could be due to concerns around circular financing tied to the SPV, customer concentration among frontier labs, or, more recently, political pushback against data centers that could slow the buildout. — Jeff Marks, CNBC, 2 Sep. 2026

Adjective

That worried Huang, who fears a Chinese rival, and White House officials, who believe Chinese dependence on non-frontier American chips is the best way to ensure a lead in AI. — Charlie Campbell, Time, 11 Dec. 2025