"сайн уу" meaning in Mongolian

{
  "forms": [
    {
      "form": "sajn uu",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "ᠰᠠᠶᠢᠨ ᠤᠤ",
      "roman": "sayin -uu",
      "tags": [
        "Mongolian"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "ᠰᠠᠶᠢᠨ  ᠤᠤ"
      },
      "expansion": "сайн уу • (sajn uu) (Mongolian spelling ᠰᠠᠶᠢᠨ\n ᠤᠤ (sayin -uu))",
      "name": "mn-interjection"
    }
  ],
  "hyphenation": [
    "сайн"
  ],
  "lang": "Mongolian",
  "lang_code": "mn",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Mongolian entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Mongolian terms with redundant script codes",
          "parents": [
            "Terms with redundant script codes",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "hello, how are you"
      ],
      "id": "en-сайн_уу-mn-intj-ipY68YN-",
      "links": [
        [
          "hello",
          "hello"
        ],
        [
          "how are you",
          "how are you"
        ]
      ],
      "raw_glosses": [
        "(informal) hello, how are you"
      ],
      "related": [
        {
          "roman": "sajn bajna uu?",
          "tags": [
            "formal"
          ],
          "word": "сайн байна уу?"
        }
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈsɛːŋ ʊː/"
    }
  ],
  "word": "сайн уу"
}

{
  "forms": [
    {
      "form": "sajn uu",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "ᠰᠠᠶᠢᠨ ᠤᠤ",
      "roman": "sayin -uu",
      "tags": [
        "Mongolian"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "ᠰᠠᠶᠢᠨ  ᠤᠤ"
      },
      "expansion": "сайн уу • (sajn uu) (Mongolian spelling ᠰᠠᠶᠢᠨ\n ᠤᠤ (sayin -uu))",
      "name": "mn-interjection"
    }
  ],
  "hyphenation": [
    "сайн"
  ],
  "lang": "Mongolian",
  "lang_code": "mn",
  "pos": "intj",
  "related": [
    {
      "roman": "sajn bajna uu?",
      "tags": [
        "formal"
      ],
      "word": "сайн байна уу?"
    }
  ],
  "senses": [
    {
      "categories": [
        "Mongolian entries with incorrect language header",
        "Mongolian informal terms",
        "Mongolian interjections",
        "Mongolian lemmas",
        "Mongolian multiword terms",
        "Mongolian terms with IPA pronunciation",
        "Mongolian terms with redundant script codes"
      ],
      "glosses": [
        "hello, how are you"
      ],
      "links": [
        [
          "hello",
          "hello"
        ],
        [
          "how are you",
          "how are you"
        ]
      ],
      "raw_glosses": [
        "(informal) hello, how are you"
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈsɛːŋ ʊː/"
    }
  ],
  "word": "сайн уу"
}