"once-in-a-lifetime" meaning in English

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      "expansion": "once-in-a-lifetime (not comparable)",
      "name": "en-adj"
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  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
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          "kind": "other",
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      ],
      "examples": [
        {
          "text": "a once-in-a-lifetime opportunity to travel the world",
          "type": "example"
        }
      ],
      "glosses": [
        "Likely to happen only once in one's lifetime; extremely rare."
      ],
      "id": "en-once-in-a-lifetime-en-adj-JGY3F4L-",
      "synonyms": [
        {
          "word": "of a lifetime"
        }
      ],
      "tags": [
        "not-comparable"
      ],
      "translations": [
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "sense": "Likely to happen only once in one's lifetime",
          "word": "千載難逢"
        },
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "roman": "qiānzǎinánféng",
          "sense": "Likely to happen only once in one's lifetime",
          "word": "千载难逢"
        },
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "Likely to happen only once in one's lifetime",
          "word": "ainutlaatuinen"
        },
        {
          "code": "fr",
          "lang": "French",
          "sense": "Likely to happen only once in one's lifetime",
          "word": "du siècle"
        },
        {
          "code": "fr",
          "lang": "French",
          "sense": "Likely to happen only once in one's lifetime",
          "word": "qui ne se présente qu’une fois"
        },
        {
          "code": "he",
          "lang": "Hebrew",
          "roman": "shél pá'am b'khayím",
          "sense": "Likely to happen only once in one's lifetime",
          "word": "של פעם בחיים"
        },
        {
          "code": "it",
          "lang": "Italian",
          "sense": "Likely to happen only once in one's lifetime",
          "word": "più unico che raro"
        }
      ]
    }
  ],
  "word": "once-in-a-lifetime"
}

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      "args": {
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      "expansion": "once-in-a-lifetime (not comparable)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
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        "Terms with French translations",
        "Terms with Hebrew translations",
        "Terms with Italian translations",
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      ],
      "examples": [
        {
          "text": "a once-in-a-lifetime opportunity to travel the world",
          "type": "example"
        }
      ],
      "glosses": [
        "Likely to happen only once in one's lifetime; extremely rare."
      ],
      "synonyms": [
        {
          "word": "of a lifetime"
        }
      ],
      "tags": [
        "not-comparable"
      ]
    }
  ],
  "translations": [
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "sense": "Likely to happen only once in one's lifetime",
      "word": "千載難逢"
    },
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "roman": "qiānzǎinánféng",
      "sense": "Likely to happen only once in one's lifetime",
      "word": "千载难逢"
    },
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "Likely to happen only once in one's lifetime",
      "word": "ainutlaatuinen"
    },
    {
      "code": "fr",
      "lang": "French",
      "sense": "Likely to happen only once in one's lifetime",
      "word": "du siècle"
    },
    {
      "code": "fr",
      "lang": "French",
      "sense": "Likely to happen only once in one's lifetime",
      "word": "qui ne se présente qu’une fois"
    },
    {
      "code": "he",
      "lang": "Hebrew",
      "roman": "shél pá'am b'khayím",
      "sense": "Likely to happen only once in one's lifetime",
      "word": "של פעם בחיים"
    },
    {
      "code": "it",
      "lang": "Italian",
      "sense": "Likely to happen only once in one's lifetime",
      "word": "più unico che raro"
    }
  ],
  "word": "once-in-a-lifetime"
}