"sewer fly" meaning in English

{
  "forms": [
    {
      "form": "sewer flies",
      "tags": [
        "plural"
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      "expansion": "sewer fly (plural sewer flies)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Dipterans",
          "orig": "en:Dipterans",
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            "Arthropods",
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      ],
      "glosses": [
        "Any of the family Psychodidae of true flies, sometimes found in plumbing drains and sewage systems."
      ],
      "id": "en-sewer_fly-en-noun-3oOxPVfX",
      "links": [
        [
          "Psychodidae",
          "Psychodidae#Translingual"
        ]
      ]
    }
  ],
  "word": "sewer fly"
}

{
  "forms": [
    {
      "form": "sewer flies",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
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      "expansion": "sewer fly (plural sewer flies)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        "en:Dipterans"
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      "glosses": [
        "Any of the family Psychodidae of true flies, sometimes found in plumbing drains and sewage systems."
      ],
      "links": [
        [
          "Psychodidae",
          "Psychodidae#Translingual"
        ]
      ]
    }
  ],
  "word": "sewer fly"
}