Definition of last frontier in English:

last frontier

noun

  • 1A part of a country, region, etc. that is the last to be settled, explored, or developed.

    ‘the deep ocean is the last frontier of exploration on this planet’
    1. 1.1US
      a nickname for the state of Alaska
    2. 1.2 The extreme limit of understanding or achievement in a particular area.
      ‘one of the last frontiers of rock 'n' roll has been instrumental music’