fron·​tier | \ˌfrən-ˈtir, ˈfrən-ˌtir, frän-ˈtir, ˈfrän-ˌtir \

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

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

After a decade of RuPaul's Drag Race, the Glamazon has another media frontier to conquer: the daytime talk show. Henry Youtt, Billboard, "RuPaul Aims for Daytime With New Talk Show Pilot," 10 July 2018 The series will tell the brutal true story of Christopher Columbus and the first Wild West frontier, the tropical Caribbean island that now encompasses the Dominican Republic and Haiti. Borys Kit, The Hollywood Reporter, "Dana Brunetti Launches New Film and TV Company Cavalry Media (Exclusive)," 26 June 2018 He is appalled at the very idea of frontier living. Christopher Arnott,, "Frontier Justice In 'Flyin' West' At Westport Playhouse," 5 June 2018 The Huntingdon Factory Huntington, Indiana, looks paused in the moment that New England met the frontier. Tom Chiarella And James Lynch, Popular Mechanics, "The Last Shift: What Really Happened To Those Carrier Jobs Trump Saved," 15 May 2018 Unions have also turned to new, sometimes unexpected frontiers to gain members. Washington Post, "Despite setbacks and high court’s ruling, unions show spark," 28 June 2018 Surely the Gateway to the West could do better, both at telling a more complex story of expansion into the frontier, and at explaining why the gateway was here in St. Louis. Alexandra Lange, Curbed, "Gateway to what?," 28 June 2018 The large-scale event brand has wowed audiences since 2005, and it's since expanded into international frontiers. Kat Bein, Billboard, "Tomorrowland Will UNITE Mini-Festivals Around the World With Live Stream," 6 June 2018 The China-America corporate rivalry on an obscure frontier of physics illustrates a growing contest between nations and companies hoping to create a new form of improbably powerful computer. Tom Simonite, WIRED, "Google, Alibaba Spar Over Timeline for 'Quantum Supremacy'," 19 May 2018

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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Statistics for frontier

Last Updated

8 Nov 2018

Look-up Popularity

Time Traveler for frontier

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

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More Definitions for frontier



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 \

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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Comments on frontier

What made you want to look up frontier? Please tell us where you read or heard it (including the quote, if possible).


to clear from alleged fault or guilt

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