"on guard" meaning in English

{
  "antonyms": [
    {
      "word": "off guard"
    }
  ],
  "forms": [
    {
      "form": "more on guard",
      "tags": [
        "comparative"
      ]
    },
    {
      "form": "most on guard",
      "tags": [
        "superlative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "on guard (comparative more on guard, superlative most on guard)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Fencing",
          "orig": "en:Fencing",
          "parents": [
            "Sports",
            "Human activity",
            "Human behaviour",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "_dis": "61 11 28",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        }
      ],
      "examples": [
        {
          "ref": "1881, Robert Louis Stevenson, Virginibus Puerisque",
          "text": "We fall on guard, and after all it is a friend who comes to meet us.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "The starting position of a fencing bout; en garde."
      ],
      "id": "en-on_guard-en-adj-ORAnr103",
      "links": [
        [
          "fencing",
          "fencing#Noun"
        ],
        [
          "en garde",
          "en garde"
        ]
      ],
      "raw_glosses": [
        "(fencing) The starting position of a fencing bout; en garde."
      ],
      "topics": [
        "fencing",
        "government",
        "hobbies",
        "lifestyle",
        "martial-arts",
        "military",
        "politics",
        "sports",
        "war"
      ]
    },
    {
      "glosses": [
        "Vigilant, alert."
      ],
      "id": "en-on_guard-en-adj-LhGLcxaL",
      "links": [
        [
          "Vigilant",
          "vigilant"
        ],
        [
          "alert",
          "alert"
        ]
      ],
      "translations": [
        {
          "_dis1": "14 77 10",
          "code": "fr",
          "lang": "French",
          "sense": "on alert, vigilant",
          "word": "en garde"
        },
        {
          "_dis1": "14 77 10",
          "code": "mi",
          "lang": "Maori",
          "sense": "on alert, vigilant",
          "word": "whakahiwa"
        },
        {
          "_dis1": "14 77 10",
          "code": "pl",
          "lang": "Polish",
          "note": "no equivalent term in Polish",
          "sense": "on alert, vigilant"
        },
        {
          "_dis1": "14 77 10",
          "code": "pl",
          "lang": "Polish",
          "sense": "on alert, vigilant",
          "tags": [
            "imperfective"
          ],
          "word": "but see mieć się na baczności"
        }
      ]
    },
    {
      "categories": [
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Aviation",
          "orig": "en:Aviation",
          "parents": [
            "Aeronautics",
            "Transport",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Transmitting on the aircraft emergency frequency."
      ],
      "id": "en-on_guard-en-adj-k7TmK8wJ",
      "links": [
        [
          "aviation",
          "aviation"
        ],
        [
          "Transmitting",
          "transmit"
        ]
      ],
      "raw_glosses": [
        "(aviation) Transmitting on the aircraft emergency frequency."
      ],
      "synonyms": [
        {
          "_dis1": "32 0 68",
          "word": "on-guard"
        }
      ],
      "topics": [
        "aeronautics",
        "aerospace",
        "aviation",
        "business",
        "engineering",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-us-on guard.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/4/41/En-us-on_guard.ogg/En-us-on_guard.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/4/41/En-us-on_guard.ogg",
      "tags": [
        "Mid-Atlantic"
      ],
      "text": "Audio (Mid-Atlantic)"
    }
  ],
  "word": "on guard"
}

{
  "antonyms": [
    {
      "word": "off guard"
    }
  ],
  "categories": [
    "English adjectives",
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English terms with audio links"
  ],
  "forms": [
    {
      "form": "more on guard",
      "tags": [
        "comparative"
      ]
    },
    {
      "form": "most on guard",
      "tags": [
        "superlative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "on guard (comparative more on guard, superlative most on guard)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "English terms with quotations",
        "Quotation templates to be cleaned",
        "en:Fencing"
      ],
      "examples": [
        {
          "ref": "1881, Robert Louis Stevenson, Virginibus Puerisque",
          "text": "We fall on guard, and after all it is a friend who comes to meet us.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "The starting position of a fencing bout; en garde."
      ],
      "links": [
        [
          "fencing",
          "fencing#Noun"
        ],
        [
          "en garde",
          "en garde"
        ]
      ],
      "raw_glosses": [
        "(fencing) The starting position of a fencing bout; en garde."
      ],
      "topics": [
        "fencing",
        "government",
        "hobbies",
        "lifestyle",
        "martial-arts",
        "military",
        "politics",
        "sports",
        "war"
      ]
    },
    {
      "glosses": [
        "Vigilant, alert."
      ],
      "links": [
        [
          "Vigilant",
          "vigilant"
        ],
        [
          "alert",
          "alert"
        ]
      ]
    },
    {
      "categories": [
        "en:Aviation"
      ],
      "glosses": [
        "Transmitting on the aircraft emergency frequency."
      ],
      "links": [
        [
          "aviation",
          "aviation"
        ],
        [
          "Transmitting",
          "transmit"
        ]
      ],
      "raw_glosses": [
        "(aviation) Transmitting on the aircraft emergency frequency."
      ],
      "topics": [
        "aeronautics",
        "aerospace",
        "aviation",
        "business",
        "engineering",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-us-on guard.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/4/41/En-us-on_guard.ogg/En-us-on_guard.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/4/41/En-us-on_guard.ogg",
      "tags": [
        "Mid-Atlantic"
      ],
      "text": "Audio (Mid-Atlantic)"
    }
  ],
  "synonyms": [
    {
      "word": "on-guard"
    }
  ],
  "translations": [
    {
      "code": "fr",
      "lang": "French",
      "sense": "on alert, vigilant",
      "word": "en garde"
    },
    {
      "code": "mi",
      "lang": "Maori",
      "sense": "on alert, vigilant",
      "word": "whakahiwa"
    },
    {
      "code": "pl",
      "lang": "Polish",
      "note": "no equivalent term in Polish",
      "sense": "on alert, vigilant"
    },
    {
      "code": "pl",
      "lang": "Polish",
      "sense": "on alert, vigilant",
      "tags": [
        "imperfective"
      ],
      "word": "but see mieć się na baczności"
    }
  ],
  "word": "on guard"
}