"5B" meaning in All languages combined

{
  "forms": [
    {
      "form": "5Bs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "5B (plural 5Bs)",
      "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"
        }
      ],
      "glosses": [
        "A grade of pencil with lead that makes darker marks than a pencil grade 4B but lighter marks than a pencil of grade 6B; a pencil with very soft lead."
      ],
      "id": "en-5B-en-noun-kgI5B~em",
      "links": [
        [
          "4B",
          "4B"
        ],
        [
          "6B",
          "6B"
        ]
      ],
      "raw_glosses": [
        "(British English) A grade of pencil with lead that makes darker marks than a pencil grade 4B but lighter marks than a pencil of grade 6B; a pencil with very soft lead."
      ],
      "tags": [
        "British",
        "English"
      ]
    }
  ],
  "word": "5B"
}

{
  "forms": [
    {
      "form": "5Bs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "5B (plural 5Bs)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English nouns",
        "English terms spelled with numbers",
        "English words without vowels",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "glosses": [
        "A grade of pencil with lead that makes darker marks than a pencil grade 4B but lighter marks than a pencil of grade 6B; a pencil with very soft lead."
      ],
      "links": [
        [
          "4B",
          "4B"
        ],
        [
          "6B",
          "6B"
        ]
      ],
      "raw_glosses": [
        "(British English) A grade of pencil with lead that makes darker marks than a pencil grade 4B but lighter marks than a pencil of grade 6B; a pencil with very soft lead."
      ],
      "tags": [
        "British",
        "English"
      ]
    }
  ],
  "word": "5B"
}