"1-555" meaning in English

{
  "etymology_text": "1, used to dial long-distance numbers + 555, the North American code for the provision of directory assistance.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "1-555 (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "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": "Fiction",
          "orig": "en:Fiction",
          "parents": [
            "Artistic works",
            "Art",
            "Culture",
            "Society",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Telephony",
          "orig": "en:Telephony",
          "parents": [
            "Electronics",
            "Telecommunications",
            "Technology",
            "Communication",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Of telephone numbers dialed in North America, widely used for fictional numbers in television shows, films, and other media."
      ],
      "id": "en-1-555-en-adj-G9bKTGvq",
      "links": [
        [
          "telephone number",
          "telephone number"
        ]
      ],
      "synonyms": [
        {
          "word": "555"
        }
      ],
      "tags": [
        "not-comparable"
      ],
      "wikipedia": [
        "555 (telephone number)"
      ]
    }
  ],
  "word": "1-555"
}

{
  "etymology_text": "1, used to dial long-distance numbers + 555, the North American code for the provision of directory assistance.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "1-555 (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "English adjectives",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English terms spelled with numbers",
        "English uncomparable adjectives",
        "English words without vowels",
        "en:Fiction",
        "en:Telephony"
      ],
      "glosses": [
        "Of telephone numbers dialed in North America, widely used for fictional numbers in television shows, films, and other media."
      ],
      "links": [
        [
          "telephone number",
          "telephone number"
        ]
      ],
      "tags": [
        "not-comparable"
      ],
      "wikipedia": [
        "555 (telephone number)"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "555"
    }
  ],
  "word": "1-555"
}