"18-wheeler" meaning in English

{
  "etymology_text": "From the total number of wheels: two front steering wheels on the tractor, plus dual wheels on each end of two axles (total of 8) at the rear of the tractor and supporting the front of the trailer, plus dual wheels on two axles at the rear of the trailer.",
  "forms": [
    {
      "form": "18-wheelers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "18-wheeler (plural 18-wheelers)",
      "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"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Eighteen",
          "orig": "en:Eighteen",
          "parents": [
            "Numbers",
            "All topics",
            "Terms by semantic function",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Vehicles",
          "orig": "en:Vehicles",
          "parents": [
            "Machines",
            "Transport",
            "Technology",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A big rig truck: a semi-trailer plus the truck or tractor pulling it."
      ],
      "id": "en-18-wheeler-en-noun-AJuPv1rq",
      "links": [
        [
          "big rig",
          "big rig"
        ],
        [
          "semi-trailer",
          "semi-trailer"
        ],
        [
          "truck",
          "truck"
        ],
        [
          "tractor",
          "tractor"
        ]
      ],
      "synonyms": [
        {
          "word": "semi-trailer truck"
        },
        {
          "word": "semi truck"
        },
        {
          "word": "semi"
        },
        {
          "word": "articulated lorry"
        },
        {
          "word": "artic"
        },
        {
          "word": "big rig"
        },
        {
          "word": "juggernaut"
        },
        {
          "word": "tractor-trailer"
        },
        {
          "word": "truck and trailer"
        },
        {
          "word": "eighteen-wheeler"
        }
      ]
    }
  ],
  "word": "18-wheeler"
}

{
  "etymology_text": "From the total number of wheels: two front steering wheels on the tractor, plus dual wheels on each end of two axles (total of 8) at the rear of the tractor and supporting the front of the trailer, plus dual wheels on two axles at the rear of the trailer.",
  "forms": [
    {
      "form": "18-wheelers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "18-wheeler (plural 18-wheelers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms spelled with numbers",
        "English terms with non-redundant non-automated sortkeys",
        "en:Eighteen",
        "en:Vehicles"
      ],
      "glosses": [
        "A big rig truck: a semi-trailer plus the truck or tractor pulling it."
      ],
      "links": [
        [
          "big rig",
          "big rig"
        ],
        [
          "semi-trailer",
          "semi-trailer"
        ],
        [
          "truck",
          "truck"
        ],
        [
          "tractor",
          "tractor"
        ]
      ],
      "synonyms": [
        {
          "word": "semi-trailer truck"
        },
        {
          "word": "semi truck"
        },
        {
          "word": "semi"
        },
        {
          "word": "articulated lorry"
        },
        {
          "word": "artic"
        },
        {
          "word": "big rig"
        },
        {
          "word": "juggernaut"
        },
        {
          "word": "tractor-trailer"
        },
        {
          "word": "truck and trailer"
        }
      ]
    }
  ],
  "synonyms": [
    {
      "word": "eighteen-wheeler"
    }
  ],
  "word": "18-wheeler"
}