"T/D" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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      "alt_of": [
        {
          "word": "top of descent"
        }
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          "name": "Aviation",
          "orig": "en:Aviation",
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            "Aeronautics",
            "Transport",
            "Sciences",
            "All topics",
            "Fundamental"
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      "examples": [
        {
          "text": "The pilots landed at the airport after reaching their T/D",
          "type": "example"
        }
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      "glosses": [
        "Initialism of top of descent."
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      "id": "en-T/D-en-noun-ewalnbvR",
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          "top",
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          "descent",
          "descent#English"
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        "(aviation) Initialism of top of descent."
      ],
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      "topics": [
        "aeronautics",
        "aerospace",
        "aviation",
        "business",
        "engineering",
        "natural-sciences",
        "physical-sciences"
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  "word": "T/D"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "top of descent"
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        "English countable nouns",
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        "en:Aviation"
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      "examples": [
        {
          "text": "The pilots landed at the airport after reaching their T/D",
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        "Initialism of top of descent."
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        ],
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      "raw_glosses": [
        "(aviation) Initialism of top of descent."
      ],
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      "topics": [
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  ],
  "word": "T/D"
}