"громъ" meaning in Vieux slave

{
  "categories": [
    {
      "kind": "other",
      "name": "Mots en vieux slave issus d’un mot en indo-européen commun",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Noms communs en vieux slave",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Vieux slave",
      "orig": "vieux slave",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Étymologies en vieux slave incluant une reconstruction",
      "parents": [],
      "source": "w"
    }
  ],
  "derived": [
    {
      "lang": "Polonais",
      "lang_code": "pl",
      "word": "grom"
    },
    {
      "lang": "Russe",
      "lang_code": "ru",
      "word": "гром"
    },
    {
      "lang": "Slovaque",
      "lang_code": "sk",
      "word": "hrom"
    },
    {
      "lang": "Slovène",
      "lang_code": "sl",
      "word": "grom"
    },
    {
      "lang": "Tchèque",
      "lang_code": "cs",
      "word": "hrom"
    }
  ],
  "etymology_texts": [
    "De l’indo-européen commun *ghrem- ^([1]) (« gronder, faire un bruit sourd ») qui donne aussi le grec ancien χρόμος, khrómos, l’allemand grummen, grummeln (« grommeler »), l’anglais grumble, le néerlandais grommen."
  ],
  "lang": "Vieux slave",
  "lang_code": "cu",
  "pos": "noun",
  "pos_title": "Nom commun",
  "related": [
    {
      "word": "грьмѣти"
    }
  ],
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Lexique en vieux slave de la météorologie",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Tonnerre."
      ],
      "id": "fr-громъ-cu-noun-Ue0rM1xW",
      "topics": [
        "meteorology"
      ]
    }
  ],
  "tags": [
    "masculine"
  ],
  "word": "громъ"
}

{
  "categories": [
    "Mots en vieux slave issus d’un mot en indo-européen commun",
    "Noms communs en vieux slave",
    "vieux slave",
    "Étymologies en vieux slave incluant une reconstruction"
  ],
  "derived": [
    {
      "lang": "Polonais",
      "lang_code": "pl",
      "word": "grom"
    },
    {
      "lang": "Russe",
      "lang_code": "ru",
      "word": "гром"
    },
    {
      "lang": "Slovaque",
      "lang_code": "sk",
      "word": "hrom"
    },
    {
      "lang": "Slovène",
      "lang_code": "sl",
      "word": "grom"
    },
    {
      "lang": "Tchèque",
      "lang_code": "cs",
      "word": "hrom"
    }
  ],
  "etymology_texts": [
    "De l’indo-européen commun *ghrem- ^([1]) (« gronder, faire un bruit sourd ») qui donne aussi le grec ancien χρόμος, khrómos, l’allemand grummen, grummeln (« grommeler »), l’anglais grumble, le néerlandais grommen."
  ],
  "lang": "Vieux slave",
  "lang_code": "cu",
  "pos": "noun",
  "pos_title": "Nom commun",
  "related": [
    {
      "word": "грьмѣти"
    }
  ],
  "senses": [
    {
      "categories": [
        "Lexique en vieux slave de la météorologie"
      ],
      "glosses": [
        "Tonnerre."
      ],
      "topics": [
        "meteorology"
      ]
    }
  ],
  "tags": [
    "masculine"
  ],
  "word": "громъ"
}