frontier

American  

[fruhn-teer, fron-, fruhn-teer] / frʌnˈtɪər, frɒn-, ˈfrʌn tɪər /

noun

1. the part of a country that borders another country; boundary; border.

2. the land or territory that forms the furthest extent of a country's settled or inhabited regions.

3. Often frontiers.

   1. the limit of knowledge or the most advanced achievement in a particular field.

      the frontiers of physics.

   2. an outer limit in a field of endeavor, especially one in which the opportunities for research and development have not been exploited.

      the frontiers of space exploration.

4. Mathematics. boundary.

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adjective

1. of, relating to, or located on the frontier.

   a frontier town.

frontier British  

/ frʌnˈtɪə, ˈfrʌntɪə /

noun

1. 1. the region of a country bordering on another or a line, barrier, etc, marking such a boundary

   2. ( as modifier )

      a frontier post

2. 1. the edge of the settled area of a country

   2. ( as modifier )

      the frontier spirit

3. (often plural) the limit of knowledge in a particular field

   the frontiers of physics have been pushed back

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Related Words

See boundary.

Other Word Forms

• frontierless adjective
• frontierlike adjective
• semifrontier noun
• transfrontier adjective

Etymology

Origin of frontier

1350–1400; Middle English frounter < Old French frontier, equivalent to front (in the sense of opposite side; front ) + -ier -ier ²

Example Sentences

“I do not believe that financial insecurity should stop our nation’s elite athletes from breaking through to new frontiers of excellence,” Stevens said.

From The Wall Street Journal

Beyond improving our understanding of melting in two dimensions, the study also shows how advanced microscopy and artificial intelligence can work together to explore new frontiers in materials science.

From Science Daily

His larger-than-life exploits and traveling shows defined America’s frontier identity and established the cowboy as a national icon, while also transforming Cody into the country’s original reality star.

From The Wall Street Journal

The island is crosshatched with invisible but palpable frontiers.

From The Wall Street Journal

He has clearly discarded the idea that the U.S. need not concern itself with matters beyond its frontiers.

From The Wall Street Journal