"rock barnacle" meaning in English

{
  "forms": [
    {
      "form": "rock barnacles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "rock barnacle (plural rock barnacles)",
      "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": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Barnacles",
          "orig": "en:Barnacles",
          "parents": [
            "Crustaceans",
            "Arthropods",
            "Animals",
            "Lifeforms",
            "All topics",
            "Life",
            "Fundamental",
            "Nature"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Semibalanus balanoides, an acorn barnacle common on rocks and other substrates in the intertidal zone of northwestern Europe and both coasts of North America."
      ],
      "id": "en-rock_barnacle-en-noun-nrV0njlg",
      "links": [
        [
          "acorn barnacle",
          "acorn barnacle"
        ],
        [
          "rock",
          "rock"
        ],
        [
          "substrate",
          "substrate"
        ],
        [
          "intertidal",
          "intertidal"
        ],
        [
          "Europe",
          "Europe"
        ],
        [
          "North America",
          "North America"
        ]
      ]
    }
  ],
  "word": "rock barnacle"
}

{
  "forms": [
    {
      "form": "rock barnacles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "rock barnacle (plural rock barnacles)",
      "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",
        "Entries using missing taxonomic name (species)",
        "Pages with 1 entry",
        "Pages with entries",
        "en:Barnacles"
      ],
      "glosses": [
        "Semibalanus balanoides, an acorn barnacle common on rocks and other substrates in the intertidal zone of northwestern Europe and both coasts of North America."
      ],
      "links": [
        [
          "acorn barnacle",
          "acorn barnacle"
        ],
        [
          "rock",
          "rock"
        ],
        [
          "substrate",
          "substrate"
        ],
        [
          "intertidal",
          "intertidal"
        ],
        [
          "Europe",
          "Europe"
        ],
        [
          "North America",
          "North America"
        ]
      ]
    }
  ],
  "word": "rock barnacle"
}