"expansion joint" meaning in English

{
  "forms": [
    {
      "form": "expansion joints",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "expansion joint (plural expansion joints)",
      "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": "topical",
          "langcode": "en",
          "name": "Construction",
          "orig": "en:Construction",
          "parents": [
            "Architecture",
            "Engineering",
            "Applied sciences",
            "Art",
            "Technology",
            "Sciences",
            "Culture",
            "All topics",
            "Society",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "coordinate_terms": [
        {
          "word": "control joint"
        }
      ],
      "glosses": [
        "A structural separation between two building elements that allows free movement between the elements without damage to the system."
      ],
      "id": "en-expansion_joint-en-noun-JQ07Q5KZ",
      "links": [
        [
          "construction",
          "construction"
        ],
        [
          "structural",
          "structural"
        ],
        [
          "elements",
          "elements"
        ]
      ],
      "raw_glosses": [
        "(construction) A structural separation between two building elements that allows free movement between the elements without damage to the system."
      ],
      "topics": [
        "business",
        "construction",
        "manufacturing"
      ]
    }
  ],
  "word": "expansion joint"
}

{
  "coordinate_terms": [
    {
      "word": "control joint"
    }
  ],
  "forms": [
    {
      "form": "expansion joints",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "expansion joint (plural expansion joints)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "en:Construction"
      ],
      "glosses": [
        "A structural separation between two building elements that allows free movement between the elements without damage to the system."
      ],
      "links": [
        [
          "construction",
          "construction"
        ],
        [
          "structural",
          "structural"
        ],
        [
          "elements",
          "elements"
        ]
      ],
      "raw_glosses": [
        "(construction) A structural separation between two building elements that allows free movement between the elements without damage to the system."
      ],
      "topics": [
        "business",
        "construction",
        "manufacturing"
      ]
    }
  ],
  "word": "expansion joint"
}