"lacustres" meaning in Français

{
  "anagrams": [
    {
      "word": "claustres"
    },
    {
      "word": "claustrés"
    },
    {
      "word": "crustales"
    }
  ],
  "categories": [
    {
      "kind": "other",
      "name": "Formes d’adjectifs en français",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Français",
      "orig": "français",
      "parents": [],
      "source": "w"
    }
  ],
  "forms": [
    {
      "form": "lacustre",
      "tags": [
        "singular",
        "masculine",
        "feminine"
      ]
    }
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "adj",
  "pos_title": "Forme d’adjectif",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Exemples en français",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "Bulletin de la Société géologique de France, 1882, page 338",
          "text": "C’est ainsi que l’étang de Caronte, qui fait communiquer l’étang de Berre avec la mer s’est creusé en suivant la base des couches lacustres fortement relevées."
        }
      ],
      "form_of": [
        {
          "word": "lacustre"
        }
      ],
      "glosses": [
        "Pluriel de lacustre."
      ],
      "id": "fr-lacustres-fr-adj-iPw-6KsR"
    }
  ],
  "sounds": [
    {
      "ipa": "\\la.kystʁ\\"
    }
  ],
  "tags": [
    "feminine",
    "form-of",
    "masculine"
  ],
  "word": "lacustres"
}

{
  "anagrams": [
    {
      "word": "claustres"
    },
    {
      "word": "claustrés"
    },
    {
      "word": "crustales"
    }
  ],
  "categories": [
    "Formes d’adjectifs en français",
    "français"
  ],
  "forms": [
    {
      "form": "lacustre",
      "tags": [
        "singular",
        "masculine",
        "feminine"
      ]
    }
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "adj",
  "pos_title": "Forme d’adjectif",
  "senses": [
    {
      "categories": [
        "Exemples en français"
      ],
      "examples": [
        {
          "ref": "Bulletin de la Société géologique de France, 1882, page 338",
          "text": "C’est ainsi que l’étang de Caronte, qui fait communiquer l’étang de Berre avec la mer s’est creusé en suivant la base des couches lacustres fortement relevées."
        }
      ],
      "form_of": [
        {
          "word": "lacustre"
        }
      ],
      "glosses": [
        "Pluriel de lacustre."
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\la.kystʁ\\"
    }
  ],
  "tags": [
    "feminine",
    "form-of",
    "masculine"
  ],
  "word": "lacustres"
}