"mainframer" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "mainframe",
        "3": "er"
      },
      "expansion": "mainframe + -er",
      "name": "suffix"
    }
  ],
  "etymology_text": "From mainframe + -er.",
  "forms": [
    {
      "form": "mainframers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "mainframer (plural mainframers)",
      "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": "English terms suffixed with -er",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1977 April 4, Computerworld, volume 11, number 14, page 16:",
          "text": "The mainframers will now have to either design or buy an interface for their systems that looks like the IBM interface.",
          "type": "quote"
        }
      ],
      "glosses": [
        "One who works with mainframe computers."
      ],
      "id": "en-mainframer-en-noun-rL14EdWe",
      "links": [
        [
          "mainframe",
          "mainframe"
        ],
        [
          "computer",
          "computer"
        ]
      ]
    }
  ],
  "word": "mainframer"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "mainframe",
        "3": "er"
      },
      "expansion": "mainframe + -er",
      "name": "suffix"
    }
  ],
  "etymology_text": "From mainframe + -er.",
  "forms": [
    {
      "form": "mainframers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "mainframer (plural mainframers)",
      "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 suffixed with -er",
        "English terms with quotations",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "examples": [
        {
          "ref": "1977 April 4, Computerworld, volume 11, number 14, page 16:",
          "text": "The mainframers will now have to either design or buy an interface for their systems that looks like the IBM interface.",
          "type": "quote"
        }
      ],
      "glosses": [
        "One who works with mainframe computers."
      ],
      "links": [
        [
          "mainframe",
          "mainframe"
        ],
        [
          "computer",
          "computer"
        ]
      ]
    }
  ],
  "word": "mainframer"
}