"couldn't" meaning in English

{
  "categories": [
    {
      "kind": "other",
      "name": "Λέξεις με επίθημα -n't (αγγλικά)",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_text": ": couldn't < could + -n't (not)",
  "forms": [
    {
      "form": "couldn't"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "examples": [
        {
          "text": "The handshakes and hugs of the two leaders couldn’t hide their mutual hostility.",
          "translation": "Οι χειραψίες και οι αγκαλιές των δύο ηγετών δεν μπορούσαν να κρύψουν την αμοιβαία έχθρα τους."
        }
      ],
      "glosses": [
        "(αρνητικό modal verb) δεν μπορούσα"
      ],
      "id": "el-couldn't-en-verb-M4m93AZI"
    }
  ],
  "word": "couldn't"
}

{
  "categories": [
    "Λέξεις με επίθημα -n't (αγγλικά)"
  ],
  "etymology_text": ": couldn't < could + -n't (not)",
  "forms": [
    {
      "form": "couldn't"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "examples": [
        {
          "text": "The handshakes and hugs of the two leaders couldn’t hide their mutual hostility.",
          "translation": "Οι χειραψίες και οι αγκαλιές των δύο ηγετών δεν μπορούσαν να κρύψουν την αμοιβαία έχθρα τους."
        }
      ],
      "glosses": [
        "(αρνητικό modal verb) δεν μπορούσα"
      ]
    }
  ],
  "word": "couldn't"
}