"hey hey" meaning in English

{
  "head_templates": [
    {
      "args": {},
      "expansion": "hey hey",
      "name": "en-interj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with language name categories using raw markup",
          "parents": [
            "Entries with language name categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English reduplications",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Greetings",
          "orig": "en:Greetings",
          "parents": [
            "Social acts",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "An informal greeting; an opening salutation."
      ],
      "id": "en-hey_hey-en-intj-kGaKMA7b",
      "links": [
        [
          "greeting",
          "greeting#English"
        ]
      ],
      "raw_glosses": [
        "(colloquial) An informal greeting; an opening salutation."
      ],
      "related": [
        {
          "word": "bye-bye"
        }
      ],
      "synonyms": [
        {
          "word": "hello"
        }
      ],
      "tags": [
        "colloquial"
      ]
    }
  ],
  "word": "hey hey"
}

{
  "head_templates": [
    {
      "args": {},
      "expansion": "hey hey",
      "name": "en-interj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "related": [
    {
      "word": "bye-bye"
    }
  ],
  "senses": [
    {
      "categories": [
        "English colloquialisms",
        "English entries with incorrect language header",
        "English entries with language name categories using raw markup",
        "English entries with topic categories using raw markup",
        "English interjections",
        "English lemmas",
        "English multiword terms",
        "English reduplications",
        "English terms with non-redundant non-automated sortkeys",
        "en:Greetings"
      ],
      "glosses": [
        "An informal greeting; an opening salutation."
      ],
      "links": [
        [
          "greeting",
          "greeting#English"
        ]
      ],
      "raw_glosses": [
        "(colloquial) An informal greeting; an opening salutation."
      ],
      "tags": [
        "colloquial"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "hello"
    }
  ],
  "word": "hey hey"
}