fron·​tier | \ ˌfrən-ˈtir How to pronounce frontier (audio) , ˈfrən-ˌtir, frän-ˈtir, ˈfrän-ˌtir How to pronounce frontier (audio) \

Definition of frontier

1a : a border between two countries the frontier between Canada and the U.S.
b obsolete : a stronghold on a frontier
2a : a region that forms the margin of settled or developed territory were sent on an expedition to explore the western frontier
b : the farthermost limits of knowledge or achievement in a particular subject frontiers in immunology
c : a line of division between different or opposed things the frontiers separating science and the humanities— R. W. Clark
d : a new field for exploitative or developmental activity … the brain lies before us as one of the last scientific frontiers here on earth.— Robert Klitzman

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Other Words from frontier

frontier adjective

Synonyms for frontier


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Examples of frontier in a Sentence

the frontier between Canada and the U.S. They were sent on an expedition to explore the western frontier.
Recent Examples on the Web The main frontier here, of course, is the international one, which follows the Rio Grande along the southern edge and, if President Trump gets his way, will eventually have a wall running most of its length. Christopher Bagley, Condé Nast Traveler, "West Texas Is More Than Just Marfa," 18 May 2020 New frontiers in the genomic revolution such as gene-editing? Sy Mukherjee, Fortune, "A coronavirus drug has already been deployed in the U.S. as the WHO declares a pandemic," 11 Mar. 2020 Reichardt illuminates life in the Pacific Northwest frontier, circa 1820, and the two men’s unlikely friendship. oregonlive, "7 must-see films at 2020 Portland International Film Festival," 25 Feb. 2020 On March 16th Germany imposed controls at most of its land frontiers, citing the need to stop the spread of the virus but also to limit cross-border panic-shopping. The Economist, "Frontier theatre Why Europe’s new border controls won’t help much," 19 Mar. 2020 In the years since, Jack has continued to offer his sage counsel to military and policy leaders, and to visit our troops on the frontiers. Jamie Mcintyre, Washington Examiner, "Top commander says Afghanistan withdrawal plan does not rely on trusting the Taliban," 11 Mar. 2020 Mexican national guardsmen and immigration agents have stepped up efforts to tighten control of the notoriously porous frontier, driving up fees smugglers charge to evade them. Dudley Althaus,, "Southern Mexico has its own “Trump Wall”," 22 Feb. 2020 Watch fashion shows and hear period music, or shop for supplies that range from the mid-1700s through the American Western frontier, such as tinware, beads, forged iron and fur. Elaine Rewolinski, Milwaukee Journal Sentinel, "Flannel Fest, Echoes of the Past Trade Show, and more to do around Wisconsin this week," 16 Feb. 2020 North Korea, which has quarantined tens of thousands and delayed the school year as precautionary steps, officially sealed its border with China in January, but smuggling across the frontier still likely happens. Time, "Defectors Cast Doubt on North Korea’s Claim It Has Zero Coronavirus Cases," 20 Apr. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'frontier.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of frontier

15th century, in the meaning defined at sense 1a

History and Etymology for frontier

Middle English fronter, from Anglo-French frountere, fronter, from front

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Time Traveler for frontier

Time Traveler

The first known use of frontier was in the 15th century

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Statistics for frontier

Last Updated

23 May 2020

Cite this Entry

“Frontier.” Dictionary, Merriam-Webster, Accessed 5 Jun. 2020.

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More Definitions for frontier


How to pronounce frontier (audio) How to pronounce frontier (audio)

English Language Learners Definition of frontier

: a border between two countries
: a distant area where few people live
: the limits of knowledge in a particular field


fron·​tier | \ ˌfrən-ˈtir How to pronounce frontier (audio) \

Kids Definition of frontier

 (Entry 1 of 2)

1 : a border between two countries
2 : the edge of the settled part of a country



Kids Definition of frontier (Entry 2 of 2)

: of, living in, or situated in the frontier frontier towns frontier families

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