"upon my word" meaning in English

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      "expansion": "upon my word",
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  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "categories": [],
      "examples": [
        {
          "ref": "1924, William Somerset Maugham, Salvatore",
          "text": "Salvatore had enormous hands, like legs of mutton, coarse and hard from constant toil, but when he bathed his children, holding them so tenderly, drying them with delicate care; upon my word they were like flowers.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Believe my words; I swear."
      ],
      "id": "en-upon_my_word-en-phrase-Me442PDR",
      "links": [
        [
          "Believe",
          "believe"
        ],
        [
          "swear",
          "swear"
        ]
      ],
      "raw_glosses": [
        "(dated) Believe my words; I swear."
      ],
      "tags": [
        "dated"
      ]
    },
    {
      "categories": [
        {
          "_dis": "28 72",
          "kind": "other",
          "name": "English entries with incorrect language header",
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            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w+disamb"
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      ],
      "examples": [
        {
          "ref": "1871, Mary Elizabeth Braddon, Fenton's Quest",
          "text": "'Well, upon my word,' exclaimed the father, taking the pipe from his mouth, and staring aghast at his daughter in a stupor of indignant surprise, 'you're a pretty article; you're a nice piece of goods for a man to bring up and waste his substance upon […]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Expressing surprise."
      ],
      "id": "en-upon_my_word-en-phrase-kAXtntd6",
      "synonyms": [
        {
          "word": "my word"
        }
      ]
    }
  ],
  "word": "upon my word"
}

{
  "categories": [
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English phrases"
  ],
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "phrase"
      },
      "expansion": "upon my word",
      "name": "head"
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  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
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        "English dated terms",
        "English terms with quotations",
        "Quotation templates to be cleaned"
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      "examples": [
        {
          "ref": "1924, William Somerset Maugham, Salvatore",
          "text": "Salvatore had enormous hands, like legs of mutton, coarse and hard from constant toil, but when he bathed his children, holding them so tenderly, drying them with delicate care; upon my word they were like flowers.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Believe my words; I swear."
      ],
      "links": [
        [
          "Believe",
          "believe"
        ],
        [
          "swear",
          "swear"
        ]
      ],
      "raw_glosses": [
        "(dated) Believe my words; I swear."
      ],
      "tags": [
        "dated"
      ]
    },
    {
      "categories": [
        "English terms with quotations",
        "Quotation templates to be cleaned"
      ],
      "examples": [
        {
          "ref": "1871, Mary Elizabeth Braddon, Fenton's Quest",
          "text": "'Well, upon my word,' exclaimed the father, taking the pipe from his mouth, and staring aghast at his daughter in a stupor of indignant surprise, 'you're a pretty article; you're a nice piece of goods for a man to bring up and waste his substance upon […]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Expressing surprise."
      ],
      "synonyms": [
        {
          "word": "my word"
        }
      ]
    }
  ],
  "word": "upon my word"
}