"tau" meaning in Tocharian B

{
  "etymology_templates": [
    {
      "args": {
        "1": "txb",
        "2": "ltc",
        "3": "-"
      },
      "expansion": "Middle Chinese",
      "name": "bor"
    },
    {
      "args": {
        "1": "斗"
      },
      "expansion": "斗 (MC tuwX)",
      "name": "ltc-l"
    },
    {
      "args": {
        "1": "en",
        "chapter": "Turkic and Chinese loan words in Tocharian",
        "chapterurl": "https://www.academia.edu/428988",
        "editors": "Bauer, Brigitte L.M.; Pinault, Georges-Jean",
        "first1": "Alexander",
        "first2": "Sergey",
        "last1": "Lubotsky",
        "last2": "Starostin",
        "pages": "257-269",
        "title": "Language in Time and Space: A Festschrift for Werner Winter on the Occasion of his 80th Birthday",
        "year": "2003"
      },
      "expansion": "2003, Alexander Lubotsky, Sergey Starostin, “Turkic and Chinese loan words in Tocharian”, in Bauer, Brigitte L.M., Pinault, Georges-Jean, editors, Language in Time and Space: A Festschrift for Werner Winter on the Occasion of his 80th Birthday, pages 257-269:",
      "name": "quote-book"
    }
  ],
  "etymology_text": "From Middle Chinese 斗 (MC tuwX).",
  "forms": [
    {
      "form": "towä",
      "tags": [
        "irregular",
        "plural"
      ]
    },
    {
      "form": "tom",
      "tags": [
        "irregular",
        "plural"
      ]
    },
    {
      "form": "taum",
      "tags": [
        "irregular",
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "txb",
        "2": "noun",
        "3": "irregular plural",
        "4": "towä",
        "5": "or",
        "6": "tom",
        "7": "or",
        "8": "taum",
        "g": "?-s"
      },
      "expansion": "tau ? sg (irregular plural towä or tom or taum)",
      "name": "head"
    }
  ],
  "lang": "Tocharian B",
  "lang_code": "txb",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 45 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Tocharian B entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "txb",
          "name": "Units of measure",
          "orig": "txb:Units of measure",
          "parents": [
            "Metrology",
            "Quantity",
            "Applied sciences",
            "Mathematics",
            "Sciences",
            "Formal sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "a dry measure, roughly equivalent to ten quarts or 1.25 pecks"
      ],
      "id": "en-tau-txb-noun-1Gj5FWHS",
      "links": [
        [
          "dry measure",
          "dry measure"
        ],
        [
          "quarts",
          "quart"
        ],
        [
          "pecks",
          "peck"
        ]
      ],
      "tags": [
        "singular"
      ]
    }
  ],
  "word": "tau"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "txb",
        "2": "ltc",
        "3": "-"
      },
      "expansion": "Middle Chinese",
      "name": "bor"
    },
    {
      "args": {
        "1": "斗"
      },
      "expansion": "斗 (MC tuwX)",
      "name": "ltc-l"
    },
    {
      "args": {
        "1": "en",
        "chapter": "Turkic and Chinese loan words in Tocharian",
        "chapterurl": "https://www.academia.edu/428988",
        "editors": "Bauer, Brigitte L.M.; Pinault, Georges-Jean",
        "first1": "Alexander",
        "first2": "Sergey",
        "last1": "Lubotsky",
        "last2": "Starostin",
        "pages": "257-269",
        "title": "Language in Time and Space: A Festschrift for Werner Winter on the Occasion of his 80th Birthday",
        "year": "2003"
      },
      "expansion": "2003, Alexander Lubotsky, Sergey Starostin, “Turkic and Chinese loan words in Tocharian”, in Bauer, Brigitte L.M., Pinault, Georges-Jean, editors, Language in Time and Space: A Festschrift for Werner Winter on the Occasion of his 80th Birthday, pages 257-269:",
      "name": "quote-book"
    }
  ],
  "etymology_text": "From Middle Chinese 斗 (MC tuwX).",
  "forms": [
    {
      "form": "towä",
      "tags": [
        "irregular",
        "plural"
      ]
    },
    {
      "form": "tom",
      "tags": [
        "irregular",
        "plural"
      ]
    },
    {
      "form": "taum",
      "tags": [
        "irregular",
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "txb",
        "2": "noun",
        "3": "irregular plural",
        "4": "towä",
        "5": "or",
        "6": "tom",
        "7": "or",
        "8": "taum",
        "g": "?-s"
      },
      "expansion": "tau ? sg (irregular plural towä or tom or taum)",
      "name": "head"
    }
  ],
  "lang": "Tocharian B",
  "lang_code": "txb",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Pages with 45 entries",
        "Pages with entries",
        "Requests for gender in Tocharian B entries",
        "Tocharian B entries with incorrect language header",
        "Tocharian B lemmas",
        "Tocharian B nouns",
        "Tocharian B terms borrowed from Middle Chinese",
        "Tocharian B terms derived from Middle Chinese",
        "txb:Units of measure"
      ],
      "glosses": [
        "a dry measure, roughly equivalent to ten quarts or 1.25 pecks"
      ],
      "links": [
        [
          "dry measure",
          "dry measure"
        ],
        [
          "quarts",
          "quart"
        ],
        [
          "pecks",
          "peck"
        ]
      ],
      "tags": [
        "singular"
      ]
    }
  ],
  "word": "tau"
}