"϶" meaning in Translingual

{
  "etymology_text": "Reversed (or backwards) version of the lowercase lunate epsilon ϵ. Introduced by Giuseppe Peano in 1889 in \"Principles of arithmetic, presented by a new method\" http://jeff560.tripod.com/set.html.",
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "10": "",
        "2": "symbol",
        "3": "",
        "4": "",
        "5": "or",
        "6": "",
        "7": "or",
        "8": "",
        "9": "or",
        "cat2": "",
        "f1lang": "en",
        "f1nolink": "",
        "f2lang": "en",
        "f2nolink": "",
        "f3lang": "en",
        "f3nolink": "",
        "f4lang": "en",
        "f4nolink": "",
        "head": "",
        "head2": "",
        "head3": "",
        "head4": "",
        "sc": "Grek",
        "sort": ""
      },
      "expansion": "϶",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "϶",
      "name": "mul-symbol"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "categories": [
        {
          "kind": "topical",
          "langcode": "mul",
          "name": "Mathematics",
          "orig": "mul:Mathematics",
          "parents": [
            "Formal sciences",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "\"such that\""
      ],
      "id": "en-϶-mul-symbol-K9ygOmnR",
      "links": [
        [
          "mathematics",
          "mathematics"
        ]
      ],
      "raw_glosses": [
        "(mathematics) \"such that\""
      ],
      "topics": [
        "mathematics",
        "sciences"
      ]
    },
    {
      "categories": [
        {
          "kind": "other",
          "name": "IPA symbols",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "A graphic variant of ⟨ɜ⟩."
      ],
      "id": "en-϶-mul-symbol-YPCvMDPC",
      "links": [
        [
          "ɜ",
          "ɜ"
        ]
      ],
      "raw_glosses": [
        "(IPA) A graphic variant of ⟨ɜ⟩."
      ],
      "tags": [
        "IPA"
      ]
    },
    {
      "categories": [
        {
          "_dis": "23 27 50",
          "kind": "other",
          "name": "Translingual entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "22 15 64",
          "kind": "other",
          "name": "Translingual terms with redundant script codes",
          "parents": [
            "Terms with redundant script codes",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A barred-ɔ for a central vowel (IPA [ɵ̞])."
      ],
      "id": "en-϶-mul-symbol-DkpCzLL1",
      "links": [
        [
          "ɔ",
          "ɔ#English"
        ]
      ],
      "raw_glosses": [
        "(Teuthonista) A barred-ɔ for a central vowel (IPA [ɵ̞])."
      ]
    }
  ],
  "word": "϶"
}

{
  "categories": [
    "Translingual entries with incorrect language header",
    "Translingual lemmas",
    "Translingual symbols",
    "Translingual terms with redundant script codes"
  ],
  "etymology_text": "Reversed (or backwards) version of the lowercase lunate epsilon ϵ. Introduced by Giuseppe Peano in 1889 in \"Principles of arithmetic, presented by a new method\" http://jeff560.tripod.com/set.html.",
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "10": "",
        "2": "symbol",
        "3": "",
        "4": "",
        "5": "or",
        "6": "",
        "7": "or",
        "8": "",
        "9": "or",
        "cat2": "",
        "f1lang": "en",
        "f1nolink": "",
        "f2lang": "en",
        "f2nolink": "",
        "f3lang": "en",
        "f3nolink": "",
        "f4lang": "en",
        "f4nolink": "",
        "head": "",
        "head2": "",
        "head3": "",
        "head4": "",
        "sc": "Grek",
        "sort": ""
      },
      "expansion": "϶",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "϶",
      "name": "mul-symbol"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "categories": [
        "mul:Mathematics"
      ],
      "glosses": [
        "\"such that\""
      ],
      "links": [
        [
          "mathematics",
          "mathematics"
        ]
      ],
      "raw_glosses": [
        "(mathematics) \"such that\""
      ],
      "topics": [
        "mathematics",
        "sciences"
      ]
    },
    {
      "categories": [
        "IPA symbols"
      ],
      "glosses": [
        "A graphic variant of ⟨ɜ⟩."
      ],
      "links": [
        [
          "ɜ",
          "ɜ"
        ]
      ],
      "raw_glosses": [
        "(IPA) A graphic variant of ⟨ɜ⟩."
      ],
      "tags": [
        "IPA"
      ]
    },
    {
      "glosses": [
        "A barred-ɔ for a central vowel (IPA [ɵ̞])."
      ],
      "links": [
        [
          "ɔ",
          "ɔ#English"
        ]
      ],
      "raw_glosses": [
        "(Teuthonista) A barred-ɔ for a central vowel (IPA [ɵ̞])."
      ]
    }
  ],
  "word": "϶"
}

{
  "called_from": "form_descriptions/1831",
  "msg": "unrecognized sense qualifier: Teuthonista",
  "path": [
    "϶"
  ],
  "section": "Translingual",
  "subsection": "symbol",
  "title": "϶",
  "trace": ""
}

{
  "called_from": "form_descriptions/1831",
  "msg": "unrecognized sense qualifier: Teuthonista",
  "path": [
    "϶"
  ],
  "section": "Translingual",
  "subsection": "symbol",
  "title": "϶",
  "trace": ""
}