"final frontier" meaning in English

{
  "etymology_text": "From the introductory voiceover of Star Trek: The Original Series: \"Space, the final frontier...\"",
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "final frontier",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2016, Phillip Swarts, “Need to know, 2016: Air Force Space Command on the final frontier”, in Air Force Times",
          "text": "Space may be the final frontier and it’s starting to get awfully crowded.",
          "type": "quotation"
        },
        {
          "ref": "2016, Chris Carter, “Hedge funds head for the final frontier”, in MoneyWeek, archived from the original on 2016-11-06",
          "text": "Hedge funds head for the final frontier",
          "type": "quotation"
        },
        {
          "ref": "2015, “The final frontier: Israel signs agreement with UN space group\"”, in The Times of Israel",
          "text": "The final frontier: Israel signs agreement with UN space group",
          "type": "quotation"
        },
        {
          "ref": "2015, “The final frontier for HACKERS: Experts reveal hi-tech extra-terrestrial cyberbattles to control surveillance satellites”, in The Daily Mail",
          "text": "Space, the 'final frontier', is rapidly becoming an extra-terrestrial battleground for corporate espionage and other types of cyber attack as hackers seek to gain commercial advantage from rival networks operating in the $330-billion space economy.",
          "type": "quotation"
        },
        {
          "ref": "2015, Glenn Harlan Reynolds, “Cashing in on the Final Frontier”, in USA Today",
          "text": "With all the troubles here on planet Earth, it’s comforting that things are at least looking up for the Final Frontier.",
          "type": "quotation"
        },
        {
          "ref": "2013, James Fallows, “Mars, Our First Outpost on the Final Frontier”, in The Atlantic",
          "text": "Mars, Our First Outpost on the Final Frontier",
          "type": "quotation"
        },
        {
          "ref": "2012, Neil deGrasse Tyson, “Back to The Final Frontier”, in Discover",
          "text": "Back to The Final Frontier",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Synonym of outer space"
      ],
      "id": "en-final_frontier-en-noun-QX7vldle",
      "links": [
        [
          "outer space",
          "outer space#English"
        ]
      ],
      "raw_glosses": [
        "(informal) Synonym of outer space"
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
            "synonym-of"
          ],
          "word": "outer space"
        },
        {
          "word": "high frontier"
        },
        {
          "word": "Last Frontier"
        }
      ],
      "tags": [
        "informal"
      ],
      "wikipedia": [
        "Star Trek: The Original Series",
        "en:final frontier"
      ]
    }
  ],
  "word": "final frontier"
}

{
  "etymology_text": "From the introductory voiceover of Star Trek: The Original Series: \"Space, the final frontier...\"",
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "final frontier",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English nouns with unknown or uncertain plurals",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "2016, Phillip Swarts, “Need to know, 2016: Air Force Space Command on the final frontier”, in Air Force Times",
          "text": "Space may be the final frontier and it’s starting to get awfully crowded.",
          "type": "quotation"
        },
        {
          "ref": "2016, Chris Carter, “Hedge funds head for the final frontier”, in MoneyWeek, archived from the original on 2016-11-06",
          "text": "Hedge funds head for the final frontier",
          "type": "quotation"
        },
        {
          "ref": "2015, “The final frontier: Israel signs agreement with UN space group\"”, in The Times of Israel",
          "text": "The final frontier: Israel signs agreement with UN space group",
          "type": "quotation"
        },
        {
          "ref": "2015, “The final frontier for HACKERS: Experts reveal hi-tech extra-terrestrial cyberbattles to control surveillance satellites”, in The Daily Mail",
          "text": "Space, the 'final frontier', is rapidly becoming an extra-terrestrial battleground for corporate espionage and other types of cyber attack as hackers seek to gain commercial advantage from rival networks operating in the $330-billion space economy.",
          "type": "quotation"
        },
        {
          "ref": "2015, Glenn Harlan Reynolds, “Cashing in on the Final Frontier”, in USA Today",
          "text": "With all the troubles here on planet Earth, it’s comforting that things are at least looking up for the Final Frontier.",
          "type": "quotation"
        },
        {
          "ref": "2013, James Fallows, “Mars, Our First Outpost on the Final Frontier”, in The Atlantic",
          "text": "Mars, Our First Outpost on the Final Frontier",
          "type": "quotation"
        },
        {
          "ref": "2012, Neil deGrasse Tyson, “Back to The Final Frontier”, in Discover",
          "text": "Back to The Final Frontier",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Synonym of outer space"
      ],
      "links": [
        [
          "outer space",
          "outer space#English"
        ]
      ],
      "raw_glosses": [
        "(informal) Synonym of outer space"
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
            "synonym-of"
          ],
          "word": "outer space"
        }
      ],
      "tags": [
        "informal"
      ],
      "wikipedia": [
        "Star Trek: The Original Series",
        "en:final frontier"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "high frontier"
    },
    {
      "word": "Last Frontier"
    }
  ],
  "word": "final frontier"
}