"mm-mm" meaning in English

{
  "antonyms": [
    {
      "word": "mhm"
    }
  ],
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "uh-uh"
      },
      "expansion": "uh-uh",
      "name": "m"
    },
    {
      "args": {
        "1": "en",
        "2": "um"
      },
      "expansion": "um",
      "name": "m"
    },
    {
      "args": {
        "1": "en",
        "2": "hem",
        "pos": "expression of hesitation"
      },
      "expansion": "hem (expression of hesitation)",
      "name": "m"
    }
  ],
  "etymology_text": "Nasalized form of uh-uh; see fuller etymology there. Compare um, hem (expression of hesitation).",
  "head_templates": [
    {
      "args": {},
      "expansion": "mm-mm",
      "name": "en-interj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "categories": [],
      "examples": [
        {
          "ref": "2008, M.J. Fredrick, Where There's Smoke",
          "text": "\"Need some help?\" She shook her head. “Mm-mm.”",
          "type": "quotation"
        },
        {
          "ref": "2009, Michael Batdorf, Pair of Jacks: A Novel, page 112",
          "text": "“Mm-mm,” I mumble, shaking my head.",
          "type": "quotation"
        },
        {
          "ref": "2013, Allison Leotta, Speak of the Devil: A Novel, page 250",
          "text": "Mia cocked her head. “This is my fiancé's second wedding. He has a daughter. So I'm not sure if I should wear something . . . more second-wedding-ish? Like a white suit?” “Mm-mm.” Mia shook her head.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "no"
      ],
      "id": "en-mm-mm-en-intj-k5Apjz-w",
      "links": [
        [
          "no",
          "no"
        ]
      ],
      "synonyms": [
        {
          "word": "uh-uh"
        }
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈm.m/"
    },
    {
      "ipa": "[ˈ(ʔ)ḿ̩.ʔm̩̀]"
    },
    {
      "audio": "en-us-mmmm.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/e/ea/En-us-mmmm.ogg/En-us-mmmm.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/e/ea/En-us-mmmm.ogg",
      "tags": [
        "US"
      ],
      "text": "Audio (US)"
    }
  ],
  "word": "mm-mm"
}

{
  "antonyms": [
    {
      "word": "mhm"
    }
  ],
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "uh-uh"
      },
      "expansion": "uh-uh",
      "name": "m"
    },
    {
      "args": {
        "1": "en",
        "2": "um"
      },
      "expansion": "um",
      "name": "m"
    },
    {
      "args": {
        "1": "en",
        "2": "hem",
        "pos": "expression of hesitation"
      },
      "expansion": "hem (expression of hesitation)",
      "name": "m"
    }
  ],
  "etymology_text": "Nasalized form of uh-uh; see fuller etymology there. Compare um, hem (expression of hesitation).",
  "head_templates": [
    {
      "args": {},
      "expansion": "mm-mm",
      "name": "en-interj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        "English interjections",
        "English lemmas",
        "English multiword terms",
        "English terms with IPA pronunciation",
        "English terms with audio links",
        "English terms with quotations",
        "English words without vowels"
      ],
      "examples": [
        {
          "ref": "2008, M.J. Fredrick, Where There's Smoke",
          "text": "\"Need some help?\" She shook her head. “Mm-mm.”",
          "type": "quotation"
        },
        {
          "ref": "2009, Michael Batdorf, Pair of Jacks: A Novel, page 112",
          "text": "“Mm-mm,” I mumble, shaking my head.",
          "type": "quotation"
        },
        {
          "ref": "2013, Allison Leotta, Speak of the Devil: A Novel, page 250",
          "text": "Mia cocked her head. “This is my fiancé's second wedding. He has a daughter. So I'm not sure if I should wear something . . . more second-wedding-ish? Like a white suit?” “Mm-mm.” Mia shook her head.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "no"
      ],
      "links": [
        [
          "no",
          "no"
        ]
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈm.m/"
    },
    {
      "ipa": "[ˈ(ʔ)ḿ̩.ʔm̩̀]"
    },
    {
      "audio": "en-us-mmmm.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/e/ea/En-us-mmmm.ogg/En-us-mmmm.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/e/ea/En-us-mmmm.ogg",
      "tags": [
        "US"
      ],
      "text": "Audio (US)"
    }
  ],
  "synonyms": [
    {
      "word": "uh-uh"
    }
  ],
  "word": "mm-mm"
}