Definition of frontier in US English:



  • 1A line or border separating two countries.

    • ‘The city is semicircled by the Sar Mountains and surmounted by an old Turkish fortress; the mountains are the frontier with Albania and Kosovo.’
    • ‘Their reactors and weapons stockpiles are vulnerable, their frontiers are poorly controlled and key segments of their security services are often corrupt.’
    • ‘The man at the centre of the puzzle was born in Torquay in 1867 and first fell in love with South America when he helped the Bolivian government to survey its frontier with Brazil.’
    • ‘The waterway has its source in western Zambia, forming the frontier between Zimbabwe and Zambia and passing through central Mozambique before it empties into the Indian Ocean.’
    • ‘From Basle to Haguenau, the River Rhine acted as the frontier between Germany and France - and also as a very formidable defensive barrier.’
    • ‘This frontier with Belarus was now set to become the eastern frontier of Nato itself.’
    • ‘The frontier between India and Pakistan ran through the Sikh homeland of the Punjab.’
    • ‘In the main agreement, Germany recognized its frontier with France and Belgium as specified in the Treaty of Versailles, along with the demilitarized status of the Rhineland.’
    • ‘The high Andes peaks constitute its natural frontier with Bolivia and Argentina.’
    • ‘At the time the Russians said he had been shot by a border guard while crossing the frontier with Finland.’
    • ‘Under his leadership in the 1840s, the Swazis expanded their territory to the Northwest and stabilized the southern frontier with the Zulus.’
    • ‘The North Korean capital, Pyongyang, was captured a month later, and the UN forces advanced towards the frontier with China.’
    • ‘Its function remains uncertain: it may have been conceived as a defensible barrier, or, more probably, as a well-defined frontier between two countries.’
    • ‘The German concentration against France had left only one army to defend the eastern frontier.’
    • ‘From the village of Barqueiros about 70 km / 40 miles upstream from Oporto, the region fans out either side of the river stretching as far as the frontier with Spain.’
    • ‘Polish border police fighting smugglers of people, drugs, tobacco, nuclear material and weapons are employing American Indian trackers to guard the frontier with Ukraine.’
    • ‘Hundreds of thousands more are believed to be waiting on the Afghan side of the frontier with no shelter and little food.’
    • ‘Two border guards patrolling the nearby frontier with Georgia have also been reported missing since Friday night.’
    • ‘Finally, in the spring of 1860 he sent the bulk of his army north to protect the frontier with the Papal States.’
    • ‘He dreamed of being part of this growing nation, of helping expand its frontiers.’
    border, boundary, partition, borderline, dividing line, bounding line, demarcation line
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    1. 1.1 The extreme limit of settled land beyond which lies wilderness, especially referring to the western US before Pacific settlement.
      ‘his novel of the American frontier’
      • ‘Now, the only Americana to die a more romantic cinematic death was the frontier in Westerns from the '70s.’
      • ‘Tom Cruise and Nicole Kidman star as two hapless criminals who embark on a land rush on the western frontier.’
      • ‘But perhaps it would be fairer to suggest that it was the frontier that failed the settlers.’
      • ‘The great slogan of the settlement of the western frontier during the middle parts of the 19th century was Get in, Get Rich, Get Out.’
      • ‘Hard country tends to bring out a frontier mentality in its settlers, and there's not much evidence of concern for the environment in Arizona.’
      • ‘Many times public houses were the first erected structures around which frontier towns grew.’
      • ‘Attempts by the British to restrict further expansion into the western frontier constituted one of the factors contributing to the Revolution.’
      • ‘The frontier mentality of moving on to fresh ground remains deeply embedded in the American psyche.’
      • ‘For years, all was quiet as the Western frontier was slowly settled by a trickle of pioneers.’
      • ‘The frontier mentality and adversarial roles are being replaced with new models of sustainability.’
      • ‘We have always said that our story is like the story of the frontier towns and the hinterland outposts.’
      • ‘Settling the American frontier was a matter of private choice, as were decisions about moving on.’
      • ‘During this era of settlement of the prairie and western frontiers, a belief in the inevitability of white men's dominance of the landscape was prevalent.’
      • ‘Americans saw little value in pushing this new frontier any further at the time.’
      • ‘Like many frontier outposts, Tombstone was a town divided.’
      • ‘Until the 1890s, the black regiments served almost entirely at remote western frontier posts.’
      • ‘I give more credit to the nameless women who settled the frontier and thus earned the right to vote in western states.’
      • ‘Differing colonial experiences and the settlement of the western frontier created strong and persistent regional political interests.’
      • ‘After the reductions following that war, the Army returned to its frontier outposts.’
      • ‘The farther west the preachers and padres rode the less evidence they found of Christianity, not just in the rail towns but also in the frontier settlements a day's ride from the depots.’
    2. 1.2 The extreme limit of understanding or achievement in a particular area.
      ‘the success of science in extending the frontiers of knowledge’
      • ‘This will change in the future as oceanic islands become more accessible and better known, but at present, for many Earth scientists, they remain at the frontiers of understanding.’
      • ‘His research has begun to make progress in this area, expanding the frontier of visual neuroscience to the field of decision-making and cognitive neuroscience.’
      • ‘I'm interested in expanding the frontiers of real-world liberty, not spinning Utopias.’
      • ‘It embodies a set of policies aimed at pushing back the frontiers of poverty, while supporting growth and creating opportunities.’
      • ‘Space telescopes and other space-based cosmological experiments are pushing back the frontiers of knowledge about the fundamental laws and history of the universe.’
      • ‘He noted the relevance of science and technology ‘to the struggle for development and pushing back the frontiers of poverty and underdevelopment’.’
      • ‘Those looking to push out the frontiers of our scientific understanding will be disappointed.’
      • ‘No, I just consider it pushing back the frontiers of Computing Science.’
      • ‘But a few intrepid researchers are still pushing back the frontiers on this most mundane of molecules.’
      • ‘The banks have been pushing back the frontiers by launching ever more innovative and competitive loans.’
      • ‘NASA is constantly reaching to cross the frontiers of human knowledge and understanding.’
      • ‘The production possibility frontier has been all but shattered with innovation and continuous improvement.’
      • ‘This is extremely four-square stuff, even by the standards of an artist never renowned for pushing back the frontiers of avant-garde sonic exploration.’
      • ‘Space exploration and exploitation is a major driving force in advancing the frontiers of knowledge.’
      • ‘The upper part of Figure 8.1 shows the production possibility frontiers for the UK and USA.’
      • ‘As a result they have pushed forward the frontiers of animal science and human medicine.’
      • ‘Science is hardly dead; as Laughlin says, the focus has merely shifted to different areas, pushing different frontiers with different tools in different quests.’
      • ‘The trick is to extend the frontiers of devolved responsibility, without falling over the edge into separatism.’
      • ‘For years, astronomers have been slowly pushing back the frontiers of the observable universe - looking further and further away in terms of distance, and further and further back in time.’
      • ‘We want to bring our students as quickly as possible to the frontier of current understanding.’
      limit, end, edge, side, farthest point, boundary, border, boundary line, bound, bounding line, partition line, demarcation line, end point, cut-off point, termination
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Late Middle English: from Old French frontiere, based on Latin frons, front- ‘front’.