"esterno-" meaning in Spanish

{
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "prefix"
      },
      "expansion": "esterno-",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "es",
          "name": "Anatomy",
          "orig": "es:Anatomy",
          "parents": [
            "Biology",
            "Medicine",
            "Sciences",
            "Healthcare",
            "All topics",
            "Health",
            "Fundamental",
            "Body"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "sterno-"
      ],
      "id": "en-esterno--es-prefix-o6ItT9wK",
      "links": [
        [
          "anatomy",
          "anatomy"
        ],
        [
          "sterno-",
          "sterno-"
        ]
      ],
      "raw_glosses": [
        "(anatomy) sterno-"
      ],
      "related": [
        {
          "word": "esternón"
        }
      ],
      "tags": [
        "morpheme"
      ],
      "topics": [
        "anatomy",
        "medicine",
        "sciences"
      ]
    }
  ],
  "word": "esterno-"
}

{
  "head_templates": [
    {
      "args": {
        "1": "es",
        "2": "prefix"
      },
      "expansion": "esterno-",
      "name": "head"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "prefix",
  "related": [
    {
      "word": "esternón"
    }
  ],
  "senses": [
    {
      "categories": [
        "Pages with 1 entry",
        "Pages with entries",
        "Spanish entries with incorrect language header",
        "Spanish lemmas",
        "Spanish prefixes",
        "es:Anatomy"
      ],
      "glosses": [
        "sterno-"
      ],
      "links": [
        [
          "anatomy",
          "anatomy"
        ],
        [
          "sterno-",
          "sterno-"
        ]
      ],
      "raw_glosses": [
        "(anatomy) sterno-"
      ],
      "tags": [
        "morpheme"
      ],
      "topics": [
        "anatomy",
        "medicine",
        "sciences"
      ]
    }
  ],
  "word": "esterno-"
}