"grass grub" meaning in English

{
  "forms": [
    {
      "form": "grass grubs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "grass grub (plural grass grubs)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Entries with translation boxes",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "New Zealand English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Maori translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Scarabaeoids",
          "orig": "en:Scarabaeoids",
          "parents": [
            "Beetles",
            "Insects",
            "Arthropods",
            "Animals",
            "Lifeforms",
            "All topics",
            "Life",
            "Fundamental",
            "Nature"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A grub, of species Costelytra zealandica, that attacks the roots of grass causing pasture damage, regarded as an agricultural pest."
      ],
      "id": "en-grass_grub-en-noun-q5~5Ixbm",
      "raw_glosses": [
        "(New Zealand) A grub, of species Costelytra zealandica, that attacks the roots of grass causing pasture damage, regarded as an agricultural pest."
      ],
      "tags": [
        "New-Zealand"
      ],
      "translations": [
        {
          "code": "mi",
          "lang": "Maori",
          "sense": "A grub that attacks the roots of grass",
          "word": "tūtae ruru"
        }
      ]
    }
  ],
  "word": "grass grub"
}

{
  "forms": [
    {
      "form": "grass grubs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "grass grub (plural grass grubs)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Entries using missing taxonomic name (species)",
        "Entries with translation boxes",
        "New Zealand English",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Maori translations",
        "en:Scarabaeoids"
      ],
      "glosses": [
        "A grub, of species Costelytra zealandica, that attacks the roots of grass causing pasture damage, regarded as an agricultural pest."
      ],
      "raw_glosses": [
        "(New Zealand) A grub, of species Costelytra zealandica, that attacks the roots of grass causing pasture damage, regarded as an agricultural pest."
      ],
      "tags": [
        "New-Zealand"
      ]
    }
  ],
  "translations": [
    {
      "code": "mi",
      "lang": "Maori",
      "sense": "A grub that attacks the roots of grass",
      "word": "tūtae ruru"
    }
  ],
  "word": "grass grub"
}