"left-brainer" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "left brain",
        "3": "-er",
        "id2": "relational"
      },
      "expansion": "left brain + -er",
      "name": "af"
    }
  ],
  "etymology_text": "From left brain + -er, due to the belief that the left side of the brain controls one's logical processes.",
  "forms": [
    {
      "form": "left-brainers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "left-brainer (plural left-brainers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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            "Entry maintenance"
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          "source": "w"
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          "source": "w"
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      "examples": [
        {
          "text": "Coordinate term: right-brainer"
        }
      ],
      "glosses": [
        "A logical-minded person."
      ],
      "id": "en-left-brainer-en-noun-R3cxgIYx",
      "raw_glosses": [
        "(colloquial) A logical-minded person."
      ],
      "tags": [
        "colloquial"
      ]
    }
  ],
  "word": "left-brainer"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "left brain",
        "3": "-er",
        "id2": "relational"
      },
      "expansion": "left brain + -er",
      "name": "af"
    }
  ],
  "etymology_text": "From left brain + -er, due to the belief that the left side of the brain controls one's logical processes.",
  "forms": [
    {
      "form": "left-brainers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "left-brainer (plural left-brainers)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        "English colloquialisms",
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms suffixed with -er (relational)",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "examples": [
        {
          "text": "Coordinate term: right-brainer"
        }
      ],
      "glosses": [
        "A logical-minded person."
      ],
      "raw_glosses": [
        "(colloquial) A logical-minded person."
      ],
      "tags": [
        "colloquial"
      ]
    }
  ],
  "word": "left-brainer"
}