"pump action" meaning in English

{
  "forms": [
    {
      "form": "pump actions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "pump action (plural pump actions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "langcode": "en",
          "name": "Firearms",
          "orig": "en:Firearms",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "langcode": "en",
          "name": "Weapons",
          "orig": "en:Weapons",
          "parents": [],
          "source": "w"
        }
      ],
      "derived": [
        {
          "word": "pump-action shotgun"
        }
      ],
      "glosses": [
        "A type of firearm action that uses a sliding handgrip to cycle the mechanism."
      ],
      "id": "en-pump_action-en-noun-1Pszs3Kc",
      "links": [
        [
          "action",
          "action"
        ]
      ],
      "related": [
        {
          "word": "falling block"
        },
        {
          "word": "bolt action"
        },
        {
          "word": "lever action"
        }
      ],
      "synonyms": [
        {
          "word": "slide action"
        }
      ]
    }
  ],
  "word": "pump action"
}

{
  "derived": [
    {
      "word": "pump-action shotgun"
    }
  ],
  "forms": [
    {
      "form": "pump actions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "pump action (plural pump actions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "falling block"
    },
    {
      "word": "bolt action"
    },
    {
      "word": "lever action"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Pages with 1 entry",
        "Pages with entries",
        "en:Firearms",
        "en:Weapons"
      ],
      "glosses": [
        "A type of firearm action that uses a sliding handgrip to cycle the mechanism."
      ],
      "links": [
        [
          "action",
          "action"
        ]
      ],
      "synonyms": [
        {
          "word": "slide action"
        }
      ]
    }
  ],
  "word": "pump action"
}