".38" meaning in English

{
  "forms": [
    {
      "form": ".38s",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": ".38 (plural .38s)",
      "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": "Firearms",
          "orig": "en:Firearms",
          "parents": [
            "Weapons",
            "Hunting",
            "Military",
            "Tools",
            "Human activity",
            "Society",
            "Technology",
            "Human behaviour",
            "All topics",
            "Human",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2012, Arnie Greenberg, A Fine Conundrum: A 'Joey Fine' Mystery, page 165",
          "text": "I had hoped that he had a .38 on him but that wasn't the case.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A standard kind of firearm designed to fire bullets that are approximately 0.38 inch in diameter."
      ],
      "id": "en-.38-en-noun-2P7V4bdg",
      "links": [
        [
          "firearm",
          "firearm"
        ]
      ],
      "raw_glosses": [
        "(firearms) A standard kind of firearm designed to fire bullets that are approximately 0.38 inch in diameter."
      ],
      "related": [
        {
          "word": ".22"
        },
        {
          "word": ".45"
        }
      ],
      "topics": [
        "engineering",
        "firearms",
        "government",
        "military",
        "natural-sciences",
        "physical-sciences",
        "politics",
        "tools",
        "war",
        "weaponry"
      ]
    }
  ],
  "word": ".38"
}

{
  "forms": [
    {
      "form": ".38s",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": ".38 (plural .38s)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": ".22"
    },
    {
      "word": ".45"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English nouns",
        "English terms spelled with .",
        "English terms spelled with numbers",
        "English terms with quotations",
        "English words without vowels",
        "en:Firearms"
      ],
      "examples": [
        {
          "ref": "2012, Arnie Greenberg, A Fine Conundrum: A 'Joey Fine' Mystery, page 165",
          "text": "I had hoped that he had a .38 on him but that wasn't the case.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A standard kind of firearm designed to fire bullets that are approximately 0.38 inch in diameter."
      ],
      "links": [
        [
          "firearm",
          "firearm"
        ]
      ],
      "raw_glosses": [
        "(firearms) A standard kind of firearm designed to fire bullets that are approximately 0.38 inch in diameter."
      ],
      "topics": [
        "engineering",
        "firearms",
        "government",
        "military",
        "natural-sciences",
        "physical-sciences",
        "politics",
        "tools",
        "war",
        "weaponry"
      ]
    }
  ],
  "word": ".38"
}