"hard as Chinese algebra" meaning in English

{
  "etymology_text": "Algebra and the Chinese language are both widely reputed as difficult to learn.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "hard as Chinese algebra (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English similes",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Very difficult."
      ],
      "id": "en-hard_as_Chinese_algebra-en-adj-Q2lCX-Ja",
      "links": [
        [
          "humorous",
          "humorous"
        ],
        [
          "difficult",
          "difficult"
        ]
      ],
      "qualifier": "simile",
      "raw_glosses": [
        "(simile, humorous) Very difficult."
      ],
      "tags": [
        "humorous",
        "not-comparable"
      ]
    },
    {
      "categories": [
        {
          "kind": "other",
          "name": "English similes",
          "parents": [],
          "source": "w"
        },
        {
          "_dis": "25 75",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "20 80",
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "15 85",
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "Very hard in texture, especially: having a very firm erection."
      ],
      "id": "en-hard_as_Chinese_algebra-en-adj-JRL8tDMs",
      "links": [
        [
          "humorous",
          "humorous"
        ],
        [
          "hard",
          "hard"
        ],
        [
          "erection",
          "erection"
        ]
      ],
      "qualifier": "simile",
      "raw_glosses": [
        "(simile, humorous) Very hard in texture, especially: having a very firm erection."
      ],
      "tags": [
        "humorous",
        "not-comparable"
      ]
    }
  ],
  "sounds": [
    {
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    }
  ],
  "synonyms": [
    {
      "_dis1": "47 53",
      "word": "hard as Chinese arithmetic"
    }
  ],
  "word": "hard as Chinese algebra"
}

{
  "categories": [
    "English adjectives",
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English uncomparable adjectives",
    "Pages with 1 entry",
    "Pages with entries"
  ],
  "etymology_text": "Algebra and the Chinese language are both widely reputed as difficult to learn.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "hard as Chinese algebra (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "English humorous terms",
        "English similes"
      ],
      "glosses": [
        "Very difficult."
      ],
      "links": [
        [
          "humorous",
          "humorous"
        ],
        [
          "difficult",
          "difficult"
        ]
      ],
      "qualifier": "simile",
      "raw_glosses": [
        "(simile, humorous) Very difficult."
      ],
      "tags": [
        "humorous",
        "not-comparable"
      ]
    },
    {
      "categories": [
        "English humorous terms",
        "English similes"
      ],
      "glosses": [
        "Very hard in texture, especially: having a very firm erection."
      ],
      "links": [
        [
          "humorous",
          "humorous"
        ],
        [
          "hard",
          "hard"
        ],
        [
          "erection",
          "erection"
        ]
      ],
      "qualifier": "simile",
      "raw_glosses": [
        "(simile, humorous) Very hard in texture, especially: having a very firm erection."
      ],
      "tags": [
        "humorous",
        "not-comparable"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "LL-Q1860 (eng)-Flame, not lame-hard as Chinese algebra.wav",
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    }
  ],
  "synonyms": [
    {
      "word": "hard as Chinese arithmetic"
    }
  ],
  "word": "hard as Chinese algebra"
}