"have a thing going on" meaning in English

{
  "forms": [
    {
      "form": "has a thing going on",
      "tags": [
        "present",
        "singular",
        "third-person"
      ]
    },
    {
      "form": "having a thing going on",
      "tags": [
        "participle",
        "present"
      ]
    },
    {
      "form": "had a thing going on",
      "tags": [
        "participle",
        "past"
      ]
    },
    {
      "form": "had a thing going on",
      "tags": [
        "past"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "have<has,,had> a thing going on"
      },
      "expansion": "have a thing going on (third-person singular simple present has a thing going on, present participle having a thing going on, simple past and past participle had a thing going on)",
      "name": "en-verb"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "Brad and Mary have a thing going on.",
          "type": "example"
        },
        {
          "text": "They’ve got a thing goin on.",
          "type": "example"
        },
        {
          "text": "They had a thing going on, but it's over now.",
          "type": "example"
        },
        {
          "ref": "1972, Kenny Gamble, Leon Huff, and Cary Gilbert, Me and Mrs. Jones, performed by Billy Paul, Philadelphia International Records:",
          "text": "Me and Mrs. Jones / we got a thing goin on / we both know that it's wrong / but it's much too strong / to let it go now",
          "type": "quote"
        }
      ],
      "glosses": [
        "To be in a casual or illicit romantic relationship."
      ],
      "id": "en-have_a_thing_going_on-en-verb-PIK~fh59",
      "links": [
        [
          "casual",
          "casual"
        ],
        [
          "illicit",
          "illicit"
        ],
        [
          "romantic",
          "romantic"
        ],
        [
          "relationship",
          "relationship"
        ]
      ],
      "raw_glosses": [
        "(informal) To be in a casual or illicit romantic relationship."
      ],
      "synonyms": [
        {
          "word": "have a thing"
        }
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "word": "have a thing going on"
}

{
  "forms": [
    {
      "form": "has a thing going on",
      "tags": [
        "present",
        "singular",
        "third-person"
      ]
    },
    {
      "form": "having a thing going on",
      "tags": [
        "participle",
        "present"
      ]
    },
    {
      "form": "had a thing going on",
      "tags": [
        "participle",
        "past"
      ]
    },
    {
      "form": "had a thing going on",
      "tags": [
        "past"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "have<has,,had> a thing going on"
      },
      "expansion": "have a thing going on (third-person singular simple present has a thing going on, present participle having a thing going on, simple past and past participle had a thing going on)",
      "name": "en-verb"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English terms with quotations",
        "English terms with usage examples",
        "English verbs",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "examples": [
        {
          "text": "Brad and Mary have a thing going on.",
          "type": "example"
        },
        {
          "text": "They’ve got a thing goin on.",
          "type": "example"
        },
        {
          "text": "They had a thing going on, but it's over now.",
          "type": "example"
        },
        {
          "ref": "1972, Kenny Gamble, Leon Huff, and Cary Gilbert, Me and Mrs. Jones, performed by Billy Paul, Philadelphia International Records:",
          "text": "Me and Mrs. Jones / we got a thing goin on / we both know that it's wrong / but it's much too strong / to let it go now",
          "type": "quote"
        }
      ],
      "glosses": [
        "To be in a casual or illicit romantic relationship."
      ],
      "links": [
        [
          "casual",
          "casual"
        ],
        [
          "illicit",
          "illicit"
        ],
        [
          "romantic",
          "romantic"
        ],
        [
          "relationship",
          "relationship"
        ]
      ],
      "raw_glosses": [
        "(informal) To be in a casual or illicit romantic relationship."
      ],
      "synonyms": [
        {
          "word": "have a thing"
        }
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "word": "have a thing going on"
}