"Janney coupler" meaning in English

{
  "etymology_text": "Patented in 1873 by Eli H. Janney.",
  "forms": [
    {
      "form": "Janney couplers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Janney coupler (plural Janney couplers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Entries with translation boxes",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Mandarin translations",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "A semi-automatic form of railway coupling allowing cars and locomotives to be securely linked together without rail workers having to get between the vehicles."
      ],
      "id": "en-Janney_coupler-en-noun-uKERQNv7",
      "translations": [
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "lang_code": "cmn",
          "sense": "Translations",
          "word": "詹尼車鉤 /詹尼车钩"
        }
      ]
    }
  ],
  "word": "Janney coupler"
}

{
  "etymology_text": "Patented in 1873 by Eli H. Janney.",
  "forms": [
    {
      "form": "Janney couplers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Janney coupler (plural Janney couplers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English eponyms",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Entries with translation boxes",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Mandarin translations",
        "Translation table header lacks gloss"
      ],
      "glosses": [
        "A semi-automatic form of railway coupling allowing cars and locomotives to be securely linked together without rail workers having to get between the vehicles."
      ]
    }
  ],
  "translations": [
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "lang_code": "cmn",
      "sense": "Translations",
      "word": "詹尼車鉤 /詹尼车钩"
    }
  ],
  "word": "Janney coupler"
}